Variable and files names often convey more than comments. Try to use good variable names. Long names are not always good, but sometimes it is important for the message to be conveyed. http://www.unix.org.ua/orelly/linux/cgi/ch16_02.htm
Avoid using the same names repeatedly, for instance if downsites is a script, it should not be the name of the database. Just like you don't want to name your kids Waqar1, Waqar2 and Waqar3, you should not name the files downsites, downsites10 and downsites2.
Golden Principles:
To get a brief overview of the golden principles, please see:
http://www.bbc.co.uk/guidelines/newmedia/technical/perl.shtml http://www.wpi.edu/Pubs/Policies/Web/CGI/guidelines.html