I know it's an easy way of doing it but i didn't find it neither here nor on google. So i was curious if there is a way to install multiple packages using pip. Something like:
pip install progra1 , progra2 ,progra3 ,progra4 .
or:
pip install (command to read some txt containing the name of the modules)
The answer is
You can simply place multiple name together separated by a white space like
C:\Users\Dell>pip install markdown django-filter
#c:\Users\Dell is path in my pc this can be anything on yours
this installed markdown and django-filter on my device. 
pip install -r requirements.txt
and in the requirements.txt file you put your modules in a list, with one item per line.
Django=1.3.1
South>=0.7
django-debug-toolbar
give the same command as you used to give while installing a single module only pass it via space delimited format
You can install packages listed in a text file called requirements file.
For example, if you have a file called req.txt containing the following text:
Django==1.4
South==0.7.3
and you issue at the command line:
pip install -r req.txt
pip will install packages listed in the file at the specific revisions.
You can use the following steps:
Step 1: Create a requirements.txt with list of packages to be installed. If you want to copy packages in a particular environment, do this
pip freeze >> requirements.txt
else store package names in a file named requirements.txt
Step 2: Execute pip command with this file
pip install -r requirements.txt
Complementing the other answers, you can use the option --no-cache-dir to disable caching in pip. My virtual machine was crashing when installing many packages at once with pip install -r requirements.txt. What solved for me was:
pip install --no-cache-dir -r requirements.txt
Source: Stackoverflow.com