Install Numix Theme/Icons on Elementary OS 0.2 (Luna)

$ sudo apt-add-repository ppa:numix/ppa
$ sudo apt-get update
$ sudo apt-get install numix-gtk-theme numix-icon-theme-circle

Install Icon packages on Fedora 20

(It's assumed that GNOME Tweak Tool is already installed in the system.)

Icons are mostly packaged in tar.gz or .ZIP file. Let's get a couple of them from http://gnome-look.org/: Square-Beam 1.0 and The Circle 0.2 and install and use them. Click on their respective download links and get the Square-Beam_1_0.tar.gz and TheCircle.zip packages.

Now, navigate to the /home/username/Downloads folder (or to whichever directory you have downloaded them to):

# cd /home/username/Downloads

Extract Square-Beam_1_0.tar.gz to the /usr/share/icons directory:

# tar xzf Square-Beam_1_0.tar.gz -C /usr/share/icons

Unzip TheCircle.zip at the /usr/share/icons directory:

# unzip TheCircle.zip -d /usr/share/icons

Next, open GNOME Tweak Tool and select one of them, say, Square-Beam

Here's a glimpse of the Square-Beam 1.0 icon set:

And of The Circle 0.2:

Install GNOME Tweak Tool on Fedora 20 (Heisenbug)

Here's GNOME Tweak Tool for you from wiki.gnome.org

A very simple command does the installation:

# yum install gnome-tweak-tool

Along with it, the gnome-shell-theme and the common light-theme-gnome (which includes Ubuntu's default Ambiance and Radiance themes) can also be installed:

# yum install gnome-shell-theme-*
# yum install light-theme-gnome

Now in GNOME shell's Activity menu, click on Utilities, and you'll find the Tweak Tool: 

Install Elementary-Tweaks on Elementary OS 0.2 (Luna)

Elementary Tweaks is an application to configure your eOS desktop. Here's how to install it:

$ sudo apt-add-repository ppa:versable/elementary-update
$ sudo apt-get update
$ sudo apt-get install elementary-tweaks

Now click on System Settings, and you'll see this new icon:

For a try, I've moved my icons 'plank' right:

Remove Old/Multiple Linux Kernels

After an update, there's always a possibility to see some more kernel entries on your GRUB on booting. A quick listing can be done:

# rpm -q kernel 

(the lastest is at the bottom, which also can be produced typing # uname -r )

We next make use of the package-cleanup tool in yum-utils to limit the number of kernels desired. If yum-utils isn't installed, do

# yum install yum-utils

Next set the number of kernels to the desired count (say, 2)

# package-cleanup --old kernels --count=2

Make the amount of installed kernels permanent
# gedit /etc/yum.conf 

and set installonly_limit = 2

Running your first "Hello World" C program in the Terminal

First check if you already have GCC (GNU Compiler Collection) installed in your system. Type # gcc --version (or # which gcc). If not, install it first: # yum install gcc or # yum install gcc-c++

Next open a text editor (GEDIT, say) and write your first C program.

# gedit hello.c

The hello.c program's source code can be something like

#include <stdio.h>

int main()
{
printf("Hello World");
return 0;
}

Next compile  and create an executable file

# gcc hello.c -o hello

Now execute your program

# ./hello

How do you know your operating system in 32-bit or 64-bit?

Run this command in the Terminal

# uname -m

If the output is x86_64, it's a 64-bit kernel. And if it's i686, it's a 32-bit kernel.

Install Pacifica theme on Elementary OS 0.2 (Luna)

$ sudo apt-add-repository ppa:elementary-br/projects
$ sudo apt-get update
$ sudo apt-get install pacifica-icon-theme

Now set the theme using the gsettings configuration tool:

$ gsettings set org.gnome.desktop.interface icon-theme "Pacifica"

If you've already installed Elementary Tweaks, the command above is not required. You can just select the Icon Theme and set it.

Find out the maximum RAM supported by your machine

Type the command

# dmidecode -t 16

or to be precise

# dmidecode -t 16 | grep "Maximum Capacity"

Check your Internet speed via the Terminal

We first need to install pip, a package manager for Python software packages ^[1].

# yum install python-pip

Next, we install the Python package called speedtest-cli 0.2.7

# pip install speedtest-cli

And finally, to get your Internet download speed, type the following command:

# speedtest-cli

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[1]. To see if you have already installed pip, type the command #pip --version. If pip is already installed, you'll get an output like pip 1.4.1 from /usr/lib/python2.7/site-packages (python 2.7)