Compaq tc series was a line of ultraportable convertible devices:
Compaq tc1000 — convertible 10.4" tablet PC (2003) HP Compaq tc1100 — upgrade of tc1100 (2004) HP Compaq tc4200 — convertible 12.1" laptop computer (2005) HP Compaq tc4400 — upgrade of tc4200 (2006)
This line was succeeded by the HP EliteBook 2700 series.