Backbround and Identification
Windows XP added a huge improvement to the user interface and was very popular upon release.
If you are unsure if your system runs Windows XP, check how old it is. The vast majority of pre-2007 systems still run this operating system since there often have crippling hardware problems or lack of driver support (and the drivers available do not run in 7).
Windows XP is End Of Life (EOL)
Microsoft no longer supports Windows XP and advises users to upgrade to a new PC. Some PC's are upgradeable, but these are few and far between relative to how many are not.
Many Windows XP machines are unable to a run more current operating system, as many of these are old enough driver support is unlikely to be present and the old hardware is not ideal.