Not to be confused with Compal Electronics. Compaq (a portmanteau of Compatibility And Quality; occasionally referred to as CQ prior to its final logo) was a company founded in 1982 that developed, sold, and supported computers and related products and services.
Windows Defender is a freeware program designed to protect against spyware and other unwanted software. Windows XP and Windows Server 2003 users who have genuine copies of Microsoft Windows can freely download the program from Microsoft's web site, and Windows Defender ships as part of Windows Vista and 7.
Cortana is one of the biggest features in Windows, and it acts much like a personal digital assistant. Cortana can do all sorts of things like display quick notifications, create reminders, help with navigation, open and interact with apps, search the web for you, etc.