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).

Use this search to help you limit by resource, date and more. Find specific types of websites, such as those created for academic purposes (.edu) or government (.gov).

An alternative search engine. "What you search for is your own business and we’d like to keep it that way. That’s why we don’t collect any personal information and therefore, have none to share."

Official support portal for Adobe products.

Official site for support and community discussion of Apple products and software.

Official community forums and knowledge base for support and discussion of Cisco products.

Site from the Linux Foundation that provides distributions, support, and community resources and news about Linux.

Portal page for web support for all Microsoft software / hardware / developer products.

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