Wikipedia is a *crowd-sourced* web encyclopedia, and a good source for locating initial definitions / lists / product dates for IT terminology & issues. Keep in mind:Wikipedia is a good starting point, but is not absolutely authoritative (because we can't know with certainty that the last edit was always valid).
A resource for applied and general sciences. Search for articles on Physics, Engineering, Astronomy, Biology, Earth Science, Chemistry and more. Includes Research Library: Science & Technology and SciTech Premium Collection.
Find the latest information and current trends in information technology, computer science, programming and robotics in 300 full-text publications with indexing and abstracts for nearly 450 publications.