Apache is a free and open-source cross-platform web server software.
Debian is a Linux software which is a free open-source software.
DoubleClick Ad Exchange is a real-time marketplace to buy and sell display advertising space.
Google AdSense is a program run by Google through which website publishers serve advertisements that are targeted to the site content and audience.
OpenSSL is a software library for applications that secure communications over computer networks against eavesdropping or need to identify the party at the other end.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.