Linux Web Windows

Enable WebGL on Chrome or Firefox

WebGL on Chrome

Enable hardware acceleration :

  • browse to chrome://settings/advanced
  • scroll to the bottom and look for Use hardware acceleration when available
    1. webgl_3
  • make sure Use hardware acceleration when available is checked 
  • if it tells you to then click the relaunch button

Check if webGL is enabled in Chrome

  • Copy paste the following in your browser’s address bar chrome://gpu
  •  Look for the WebGL item in the Graphics Feature Status list
    1. webgl_4
  • The status will be one of the following:
    1. Hardware accelerated — WebGL is enabled and hardware-accelerated (running on the graphics card).
    2. Software only, hardware acceleration unavailable — WebGL is enabled, but running in software.
    3. Unavailable — WebGL is not available in hardware or software.
  • You are looking for the status to be #1 from the above list i.e. Hardware accelerated


WebGL on FireFox

Enable WebGL

  • Copy paste the following in your browser’s address bar about:config
    1. you will be asked to accept a scary warning, I am positive this will be ok unless you start going godzilla or the hulk on unrelated settings 🙂 so.. dont do that.
    2. webgl_ff_1
  • Search for webgl.disabled
  • make sure that its value is set to false
    1. webgl_ff_2

Check WebGL status on FireFox browser

  • Copy paste the following in your browser’s address bar about:support
  • Inspect the WebGL Renderer row in the Graphics table
    1. webgl_ff_3
  • The status can be either of two things
    1. the name of a  graphics card manufacturer, model and driver i.e. Google Inc. — ANGLE (NVIDIA GeForce GTX 980 Ti Direct3D11 vs_5_0 ps_5_0)
    2. Something along the lines of BLocked due to version or Blocked due to unresolved issues.
  • Obviously you want #1 as the result i.e. a working webgl.
Linux shell

Ubuntu & Bash tutorial & basic utilities

An introduction to the CLI (Command Line Interface) and Bash on Ubuntu Linux aka a bash tutorial

The default shell that is installed on Ubuntu Linux is bash. Alternatives exist, but they’re beyond the scope of this tutorial (check our post here for more info on how to isntall a better alternative to bash called Zshell or zsh). Bash is available on almost all Linux distributions, so this tutorial will work on most Linux distributions as well.

What is a shell? Simply put, the shell is a program that takes your commands from the keyboard and gives them to the operating system to perform. In the old days, it was the only user interface available on a Unix computer. Nowadays, we have graphical user interfaces (GUIs) in addition to command line interfaces (CLIs) such as the shell. Bash is the most popular shell application for Linux, and is the default on Ubuntu and hundreds of other Linux distributions, Mac OS X, and soon Windows 10.

The basics are:

  • You type one or more command(s), hit enter, and it runs the command(s).
  • Use the up/down arrows to go through your bash history. Ctrl+P also works
  • Use Ctrl+R to search the history of commands used previously.
  • Hitting tab will autocomplete commands.

Instead of typing
cd ~/myfolder1/
you can just type
cd ~/my<tab>
and it’ll either autocomplete fully or if there are still more folders (like my234 and myfolder1), it’ll show you your options. You can enter multiple commands by separating them with “;” or “&&”. ; allows commands to run one after another, && runs next command only if first succeeds. For clarity, we will focus only on single commands.

Bash and Linux in general is case sensitive. That means you can have new_folder, New_folder, NEW_FOLDER, and new_Folder all in the same directory. If the computer says a file or folder doesn’t exist, you should check to see if you forgot to capitalize something. This is another good use of tab complete!

The gist of it is that a command takes in arguments/parameters, so you enter your command, add a space, add your arguments. An argument CANNOT HAVE SPACES. A space means that the argument is done and you’re putting in another argument. To circumvent this, you have two options:

  1. Escape all spaces by using a backslash (\). This is the foolproof method that will work every time. Tab autocomplete will put these in for you.
    cd My\ Really\ Annoying\ Folder\ Name
  2. Put the argument in quotations (Works 99% of the time)
    cd “My Really Annoying Folder Name”

Here are the basic things that you’ll need to know how to do to get around.

Commonly used commands

commandWhat it doesExamples
manWith man, you can retrieve the information in the manual about a command and display it as text output on your screenman ls,
page-up/down or arrow keys to browse, q to quit, / to search
lsLists all the files and folders in the current directory.

Commonly launched with arguments -lsah for better output formatting.

ls Documents
text.txtls -lsah Documents

total 3

  0 drwxr-xr-x+  76 username group   2.5K Apr 19 18:52 .

  0 drwxr-xr-x    6 root admin   204B Dec 24 01:01 ..

  8 -r——–    1 username group     7B Nov 10 20:41 text.txt

cdChanges directory. To go up a directory, its cd .. (two periods). cd with no parameters sends you to your home folder.

Using ~ will change you to your home directory and – will return to your previous working directory.

cd ..
cd my_folder
rmDeletes files. Will delete folders recursively too with the -r option.

The -f option will forcefully remove files without warning
Common meme is telling people to rm -rf /, DON’T !

rm my_file.txt
rm -r my_folderrm -rf my_folder #forcefully removes a directory and its contents
rm –no-preserve-root -rf / #This will recursively forcefully remove all files from your filesystem, don’t do it.
rmdirRemoves an empty directory (Note: Doesn’t work for non-empty directories)rmdir test #Removes test directory
cpCopies files and directories. Use -R for copying directories.cp my_file.txt my_file_copy.txt

cp my_file.txt directory/my_file.txt

cp -R my_folder my_folder_copy

mvMoves files and folders. Also the way to rename things in the command my_file.txt this_subdirectory/my_file.txt

mv my_old_foldername my_new_foldername

pwdPrints what folder you’re in. Sort of useful, but your shell should have the folder you’re in.pwd
!!Re run the last command.
This can be combined with other commands.


cd ..




sudoRuns a command as a different user, by default root. Does not work with cd.mkdir folder

mkdir: cannot create directory ‘folder’: Permission denied
sudo mkdir folder

(You will be asked for a password and the permission issues should go away)
sudo !!

[sudo] password for user:

(this does the same thing as above)

mkdirMakes a directorymkdir folder
chmodChanges file permissions (read, write, execute) + to add the permission to your user, – to remove.chmod +x myprogram
chmod -xchmod 777 filename.txt (Allow anyone to edit)
nanoThe easiest command line text editor. No arguments opens it just like opening notepad.exe without opening with a file.

Type ctrl+o to save, and ctrl+x to exit.

nano mytextfile.txt
passwdChange your password. (often has be run as root or be preceded by sudo )passwd

Changing password for <user>

(current) UNIX password:guest

Enter new UNIX password:hunter2

Retype new UNIX password:hunter2

catConcatenate two (or one) files or print everything in a file. Not recommended for viewing files, use less for that my_file.txt

<content of my_file.txt appears on screen>

headPrint the first 10 lines of a text file.head my_file.txt
tailPrint the last n lines of a text file. Super useful for log files.

If it is invoked with the argument -f it lets you continuously view the file in real time.

tail -n 10 -f logfile.txt
lessAllows you to view a text file without editing it.

Can also view log files using +F (similar to tail -f)

less my_file.txt

less +F logfile.txt

grepAllows you to use regular expressions to search through the output of a program or a file. Search for text in all files in a folder with the “-r” switch.grep ‘Error:’ my_file.txt
grep -r `find me’ my_directory/
tarExtract files from tar archives.

Common options:

tar -xzf : extract files from gzip compressed tar archive

tar -xjf : extract files from bzip2 compressed tar archive

tar -xzf system_backup_2016_04_07.tar.gz

Best way to remember tar -flags
Modern versions are smart enough to detect the format, so you can use -xf or -cf (eXtract File, Create File)

touchCreate an empty file with the specified name if the file does not exist.

Will also update the file date of an existing file without modifying the content

topTerminal-based GUI for viewing processestop
lnUsed for creating links (shortcuts) in the filesystem.
In general always use -snf (trust me)
ln -snf /opt/foo /usr/bin/bar
/usr/bin/bar now links to /opt/foo, and it is transparent to the operating system.
screenscreen let’s you run multiple login sessions in the same terminal. Say you want to run a process, you can launch it through screen, detach it, and then later come back to the same process.

When inside a screen session, type CTRL+A, then CTRL+D to detach it (put it into the background).
When you later want to reattach to the screen session, type screen -r. If you only have one screen session, you will be brought right back, otherwise you will have to specify the session id

screen bash

screen -r

screen -ls

There are screens on:

767.ttys000.localhost (Detached)

844.ttys002.localhost (Detached)

2 Sockets in /var/some/folder/random/T/.screen.

screen -r 767.ttys000.localhost

whoamiPrints the currently logged in user.whoami


whereisPrints the location of a command.whereis echo


whichPrints the location of a command.which echo


echoOutputs text to the command line. Useful when writing shell scripts.echo “hello world”

Hello world

killAttempt to terminate processkill (process id)

*if ineffective, try kill -15 or kill -9 if 15 does not work (kill -9 will forcibly terminate almost any process)

killallWill attempt to terminate a process. killall firefox
fileShows you the file typefile my_file.txt

my_file.txt: UTF-8 Unicode text

dateShow the current date in text formdate

Tue Apr 19 15:31:54 CDT 2016

psDisplay information about processes (different than top…) ps -ef
can also search for processes: ps -ef | grep firefox
aproposFind commands that do a given task, Will return a list of commands that have the searched parameter in their man file.
Note: similar functionality to running  “man -k command”.
apropos remove
Colrm (1) – remove colums from a fileCut () – remove sections from each line of files

apropos concat
cat (1)           – concatenate files and print on the standard output

cat (1p)          – concatenate and print files

eval (1p)         – construct command by concatenating arguments

aliasVery useful for creating custom shorcuts for commonly used programs or parametersalias lcolor=’ls –color=auto’
Now lcolor is the same as ls –color=autoBut shorter
envList environment variables / set environment variablesenv



The filesystem in a nutshell

“Everything is a file”. In Linux, everything is treated as a file, even your devices.

Unlike Windows and DOS, Unix systems and Linux do not have drive names. Your thumb drive will be mounted as a “folder” on Linux – Instead of being F:\ on Windows, it would be /media/<username>/my_thumbdrive, assuming that is the device name on linux. On Ubuntu, drives are usually mounted in the /media folder under your username. All your shared folders in Virtualbox will show up there, but not under your username.

/home Where your user files are stored (equivalent of C:\Users)
/media Where drives are mounted (In Ubuntu)
/bin Where system executables are stored (almost the equivalent of system32)
/lib Where the system stores the library files (like the .dll’s in system32)
/usr/bin Where extra stuff you install is stored, like python (almost equivalent of C:\Program Files)

/etc Where configuration files for various programs and network services are stored

(Equivalent to where C:\Program Files\ApplicationName files are stored)

/dev Where all the systems devices can be found. Since everything is a file in Linux, every hardware device also has a corresponding file under /dev

/tmp Where temporary files are stored (This is wiped upon reboot, unless configured otherwise)

/var Variable files—files whose content is expected to continually change during normal operation of the system—such as logs, spool files, and temporary email files.
/proc Where you can query the hardware for information e.g. cat /proc/cpuinfo
Your home folder location can be referred to as ~. So instead of typing out /home/me, you can just type ~ , and it’ll resolve to be the same path.

And that’s about the extent you need to know, and probably more so to be honest. /home/<username>/bin is a good place to store any shell scripts or whatnot that you want to run from any folder. Which brings us to our next topic…
Running your own scripts

Earlier in the table of commands, I mentioned the chmod command. Files created by you will almost always be only read write permission level, which is great from a security standpoint. However, say you want to run a python script. You could do python but that’s cumbersome. Instead, let’s do it the Linux Way™.

Header comment

The official name is the “shebang”, but in this guide I’ll call it the header comment – it’s a special type of comment you put at the top of a script in a Linux environment to tell the shell what  program to execute your program with. For a python script, you do this:

#!/usr/bin/env python

If we were writing a perl script, we would do

#!/usr/bin/env perl

If you were to write a bash script we would do:

#!/usr/bin/env bash

What it’s telling the shell to do is to look in the environment settings of the linux install, figure out where python is installed, and then run the rest of the source code through the python executable. This method has the benefit of not only being extremely portable (python might not be installed in the same place on all linux systems), it’s also super easy to remember what to write each time if you deal with multiple programming languages.

Linux doesn’t care about file extensions

With the header comment written, we now don’t have to worry about putting .py at the end of the filename anymore. You could name it “mypythonscript.jpg” if you wanted to – the data inside it is the same, and Linux just looks for that header comment, so it really doesn’t matter. It’s super nice to have no extension though, especially if you run the script a lot. You’ll just have to have your python scripts organized in a separate folder if you’re going to start foregoing extensions – hard to tell file types apart with no extension. The ‘file’ command can be used to identify which type of file a file is if you prefer to have no extensions.

Running your script

The first thing you have to do is mark it as executable. To do so, we’re going to use our trusty chmod command. We want to mark it as executable, so we’re going to use the u+x argument to add executable permissions to the file – This tells Linux to change the file mode to executible by the user only.

chmod u+x

Now, our script is executable. You can verify this by running ls, and it will now be green. Green means an executable file. To run it, we’re going to do


This is a security measure put in place by Linux so that you can be sure you are executing the file within the current directory – imagine if someone placed a malicious executable named ls in a folder, and you ran ls, and instead of executing the one in /bin, it ran the malicious one in your current folder? It wouldn’t be good.

In Linux, a single period is your current directory, and two periods is the parent directory. So


is really


If you have a script you do want to run from anywhere, put it in your bin folder in your home folder (~/bin). If you want to make that script or executable available for all users on the system, place it in /usr/local/bin.

Cancelling a process in terminal

To stop a process, hit CTRL+D. This will exit out of the current program (if you’re in an interactive python process, or if there’s a program you want to force quit in general, just hit CTRL+D) If that doesn’t work, use CTRL+C, but that isn’t a nice way of stopping a program, and its not recommended. Use as a last resort.

Previously, it was mentioned you can run multiple commands by either separating them with “;” or “&&”. The difference is that if you separate with a semicolon, you will have to force stop each command; For example if I run the following:

./; cp script_output backup/script_output; ./

If you force quit the instance of, it will continue on to copy the script_output file, which you’d have to force quit as well, as well as the A nice feature is that if has an error and fails, it will not continue on to run the copy command or the second python script.

Alternatively, if you use && to run multiple commands:

./ && cp script_output backup/script_output && ./

Now, when you cancel any one of these processes, the remaining processes will also be cancelled. However, if encounters an error, it will continue to run the second and third commands which may not be good – If cp ends up running the computer out of disk space and the second script generates more data, this could end badly. Choose the method of running multiple commands wisely. Personally I like using the && method better simply because I can force quit all of it.

To paste into the terminal, you must use CTRL+SHIFT+V. CTRL+V will not work to paste. Similarly, copying in the terminal must be CTRL+SHIFT+C.

Be careful when pasting commands into the terminal! If there’s a new line at the end of the command, it’ll automatically run the command!! (like if you hit enter after typing a command).

Multiline commands can be separated with \<enter>


cd \


Is the same As “cd /var/log” only in two lines, useful for long commands.

Package manager

No linux tutorial would be complete without an introduction to the package manager. This is a unique feature of linux – it allows you to install, update, and remove any piece of software on your computer. The syntax is very simple too. All package management must be run as root, or with “sudo” before it.

Apt – Advanced Package Tool

CommandWhat it doesExample
sudo apt updateUpdates the list of available software to install (if a security update for python got released yesterday, running update will let your computer know that)
sudo apt upgradeUpdates the installed software on your computer (applying that python security patch that it found out about through update)
sudo apt installAllows you to install a packagesudo apt install python3
sudo apt removeAllows you to remove a packagesudo apt remove vim
aptitudeLaunches the synaptics package manager – good for searching for packages. Can be run without root, but you can’t install anything without running as root.
Q to quit.
sudo aptitude

Older tutorials will use apt-get, which has since been superseded by Apt. Apt-get will still work fine, but apt is the new standard, and it has some nice improvements.

To easily search for packages in the repository, you can use Synaptic Package Manager, or you can

just google “how to install x on ubuntu” and you’ll find the package name. You can try guessing a package name, but you might not always be successful.

Pip is also directly accessible through the command line for python. Just run

sudo -H pip install

Python virtual environment

On your own machine, you have full root access, but on a work machine you most definitely will not. Having a python virtual environment allows you to install as many python packages with pip as you want, without needing to run sudo pip install <package>.

A good rule of thumb is to create a virtual environment for every project, separately, to separate dependencies from one environment to another.

An easy way to create virtual environments is to globally install a pip package called virtualenvwrapper.

To set up a virtual environment of python, create a directory in your home folder that you want the virtual environment to live in. Then run the following commands to create the virtual environment.

sudo pip install virtualenv

virtualenv pythonv

To make the python virtual environment your default python environment in your session, simply run

source /path/to/pythonv/bin/activate

Now when you run which python it will output /path/to/pythonv/bin/python.

Note that this is a temporary change – Closing the terminal or logging out will revert this change. Adding this to your ~/.bashrc file will execute it upon login, or you can set it as an alias in your bashrc.

Shell piping and redirecting IO

There are three types of pipe characters: <, >, and |. < is difficult to explain, so I left it out.

Pipe/Redirect characterWhat it doesExamples
>Redirects output to a fileman -k search > man_output.txt
>>Redirects output to file and appendsman -k find >> man_output.txt
|Takes the output of process A and puts it as input into process Bcat man_output.txt | grep “fast”
&>Redirect both standard output and error to same file.txt &> output.txt

In Linux, you have two main pipes – Standard Output (stdout, all your normal output of things that are printed to the screen), and Standard Error (stderr, when something doesn’t work right – Error on line 2, ‘;’ expected)

stdout is numbered pipe 1, and stderr is numbered pipe 2. By default, > is actually 1> – It’s redirecting standard output. If we wanted to redirect standard error, we would do 2>. 2>> will append, just like >> does. If we want to redirect both error and output, we can do &>.
This post and ubuntu / Linux / bash intro tutorial is based on work by mcvittal of reddit who licensed it under the WTFPL – Do What The Fcuck You Want To Public License. This post is here for archival and informational purposes.


virustotal api policy changes to curb one sided usage

Virustotal is a webapp that lets you upload files to check them for viruses before you install them. You can also scan a URL directly or search the VirusTotal database. The great thing about virustotal is that it checks the uploaded file against many commercial antivirus and malware detection engines not just one, and then it tells you which ones detected the file as malware.  Consequently lots of people, companies, websites, & tools have started to make use of this amazing tool to bolster their virus and malware detecting capabilities. If, for example, multiple high rated engines detect a file as suspect, then we can be certain it requires a further inspection.

The Issue at hand is that many companies have taken this service as granted. They use the results provided by virustotal as is or with little to no face checking and due diligence on their part. In some cases their own detection engines are so lack luster that it is actually better for everyone involved that they don’t bother. However this does cause a bit of an issue as this is rather unfair. Some companies and products are basically taking whats put on virustotal by other providers, checking results against those but not putting their own engines on virustotal so no one can benefit from that extra bit of checking. Dont get me wrong, every one of these product pays for a Virustotal API access subscription, but that subscription relies on a lot of great people and companies making their engines available to VT , which in turn improves the results and detection overall for the average Joe like me.

Virus total has now changed their policy to make some issues clearer and to make some things mandatory.

  • Virustotal is not a replacement for a proper antivirus.
  • Virustotal isnt intended to be a proper replacement for a full on AV product, as it doesnt have a full on Antivirus environment just the basic detection engine, hence it shouldn’t be used to rank or rate AV products of their engines.
  • Dont use third party names in your product without talking to and getting permission from the third parties, such as the engine developers etc who provide the results for virtustotal.
  • Dont use virustotal logo, name, or trademark anywhere without virustotal’s prior permission.

Biggest change that will certainly sink a few products out there :

  • all scanning companies will now be required to integrate their detection scanner in the public VT interface, in order to be eligible to receive antivirus results as part of their VirusTotal API services.
  • Additionally, new scanners joining the community will need to prove a certification and/or independent reviews from security testers according to best practices of Anti-Malware Testing Standards Organization (AMTSO)

Simply put, ALL scanning companies and end point makers will not be forced to put up their detection scanners and engines for VT to be put on their public interface, i.e. the interface you and I use, before these scanning companies can use Virustotal API. These companies cant just take everyone’s hard work and build multi million dollar companies on top of that. they have to contribute to this community effort before they can benefit from it.

Any new players on the scene will have to be vetted and certified by a governing body, in this case that would be the Anti Malware testing standards organization (AMTSO). In theory this makes it so there are some standards to be maintained.

Time shall tell how well this change works out for everyone and We shall see!

Linux shell

Alsa CLI Volume control

I couldn’t find the silly volume control in the system settings one day so i figured there had to be something I could use to control volume settings like mic boost without needing a gui or remembering names and numbers for the CLI. well there is and it’s so easy a caveman could do it (hah remember those ads….)…. so without further ado here’s a fun and great way to control your volume via Alsa CLI Volume control.

type the following then use your arrows to move right/left and make the volume higher or lower by using up/down keys:

alsamixer -c 0

the 0 at the end is the number of your device. if a system only has one device you will use 0. if you have two devices you can use 0 or 1. it tells you the name of the device currently being edited so you don’t give yourself a heart attack by changing the wrong volume. picture of the control is attached.

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General Linux

Ubuntu 16.04 release changes & info

Ubuntu 16.04, code-named “Xenial Xerus“, is here and its amazing! many new changes, many new additions and some removals of old outdated software/functionality. Unity has been polished and streamlined along with the much maligned ads have been removed! so lets get into the details.

Snap Packages

Ubuntu 16.04 LTS introduces a new application format, the ‘snap’, which can be installed alongside traditional deb packages. These two packaging formats live comfortably next to one another and enable Ubuntu to maintain its existing processes for development and updates. In short you can now install third party apps or who desktop environments without having to worry about polluting your OS! Everything stays confined away from the rest of the system in a nice little self contained environment yet still allows access to the rest of the system. So you have

  • Apps can install with their own specific set of libraries and dependencies without issues with other existing apps or ones you may install in the future.
  • Safety & security are bolstered across the board.


As with any ubuntu upgrade there are many package upgrades and software changes.

  • Ubuntu now defaults to kernel 4.4+
  • python2 is out and python 3.5 is now the base. you can still install python 2 but python 3 is the new norm. Vim by default now uses python 3.
  • Golang is now using th 1.6 toolchain.
  • With the recent discoveries in vulnerable crypto settings in openssh, the new base OpenSSH 7.2p2 disables many to bolster security.
  • the GNU toolchain is now updated to latest version of many tools.


“Controversy ahoy Cap’n!” ZFS is now included with ubuntu and how happy are we all to see it so. ZFS is a pretty cool piece of tech that is a mix of a volume manager and a filesystem. So think of LVM and EXT4 having a nerdy baby! lots of distros have supported ZFs before but not usually out of the box, almost all required installed software/libraries or using fuse, which comes with its own overhead. Find out more about Ubuntu 16.04 support for ZFS here.


Many of us are waiting for Unity 8 which brings with it a slew of changes such as Convergance which allows unity to handle both desktop and mobile environments and interfaces. However that day is not yet here. We are getting a polished, cleaned up unity 7.4 which comes with many changes.

  • The online search ads based on your search results are gone! dead! goodbye!
  • the launcher can be moved to the bottom of the screen.
  • Ubuntu software center is gone! replaced by Gnome software center
  • Empathy IM is gone.
  • Improved launcher integration with file manager and devices
  • Support for formatting removable devices from quicklist
  • Improved support for gtk applications using headerbars
  • Improvements to the switcher and spread backends
  • App spread shortcut is now Super+Ctrl+W
  • Unity control center option to always show menus
  • Improvements to GNOME key grabbing
  • New dash overlay scrollbars
  • Better Dash theming support
  • Improved Support for HiDPI environments
  • Show icons launching state in launcher when apps launched elsewhere

All in all Ubuntu 16.04 Xenial Xerus is a must have version of Ubuntu. Check below to download it.

Click here to download directly as ISO via HTTP from Canonical : [button link=”” color=”orange” newwindow=”yes”] Click to download Xenial Xerus[/button]

Linux shell

Linux distribution info & kernel info

Do you have multiple vms and real machines you use for random testing, and small tasks? need to know what machine you are on? what kernel you are using? what the current Linux distribution info is? what OS version did you last install on here? and more such questions? well! we have some of the answers for you. well maybe not answers, but more like small tools so you can get the answers!

Distribution info

lsb_release -a
on my ubuntu system it gives the following result :

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu Xenial Xerus (development branch)
Release: 16.04
Codename: xenial

On a debian system it gives the following result :

# lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 8.4 (jessie)
Release: 8.4
Codename: jessie

If lsb_release -a doesn’t cut it for you then you can try
cat /etc/issue

as a result we see the following examples :

# cat /etc/issue
Debian GNU/Linux 8 \n \l

$ cat /etc/issue
Ubuntu Xenial Xerus (development branch) \n \l

In some cases where you suspect you are on centos or redhat, maybe because you noticed the package versions are old enough to be used by columbus while sailing the open seas, then you can use either

cat /etc/centos-release


cat /etc/redhat-release

which will give you result such as :

CentOS release 6.2 (Final)

Kernel Info

now as far as finding the kernel info goes you can get all the info you need via uname.

$ uname -a
Linux testhost 4.4.0-9-generic #24-Ubuntu SMP Mon Feb 29 19:33:19 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
$ uname -r

as you can see uname -r gives you just the kernel version and uname -a gives you multiple pieces of info, like date the kernel was compiled, the arch (i.e. x86_64).