How to set up proxy authorization in Ubuntu Linux

If your net connection is proxy authenticated or needs username and password to a connect to the net, then you need to configure the network settings to access the internet. When there are proxy settings and username & password are required for internet, here are the few simple steps to setup the proxy authorization for Ubuntu.

1. Goto Terminal and type sudo nautilus.
2. A folder window will appear, from there go to filesystem->etc->apt->apt.conf 
3. Type the following  
http://<proxy address> <username>:<password>@<proxy address>:<port number>

e.g. http://172.18.0.10 admin:adminpassword@172.18.0.10:3122 

If you have any queries, do post below as comments....