PIC is Pilot in Command Time. This is time you log during solo flights, flights operated using your Private or Commercial certificate, flights operated as a CFI, etc. This does not include flights when you are being given flight instruction by a CFI.
SIC is second in command time. This is time you log when you are operating as a First Officer on an aircraft that requires two pilots.
TPIC is time you can log when operating a Turbine powered aircraft as Pilot in Command. This includes most jet powered aircraft and Turbo Props. You must possess an ATP rating and a type rating for the aircraft you are operating. Also you must be the person you signs for the aircraft as the Captain.
All time is valuable. Total time is very important. Most major airlines used to require 1000 hours of TPIC to even apply. Now that requirement is gone, however it is still an important milestone to be competitive at most Legacy carriers. In the last several, many people have been hired without any TPIC by legacy airlines, however unless you possess some other impressive qualification (think chief pilots son, winner of a major airline scholarship, interned in flight ops at a legacy airline). You should still plan on upgrading to Captain and building that 1000 TPIC.