Open Source software is a type of software that may be altered, tweaked and added to in order to improve upon its performance and function. According to howstuffworks.com some software such as compiled software is tricky to rewrite. However open source software actually encourages you to modify its code. There are several open source codes out there that are well known and waiting to be tweaked and rewritten by us.
Some of these open sources consist of programs such as Fire Fox according to howstuffworks.com. Fire Fox is a well known web browser that actually allows the user or developer to view and modify the source code. According to howstuffworks.com PERL (a scripting language), and APACHE (A web server) are also open source. There are many open source programs out there that are just itching to have your personal touch to improve them. Give it a shot.