Tertiary Sources Tertiary sources are publications that summarize and digest the information in primary and secondary sources to provide background on a topic, idea, or event. Encyclopedias and biographical dictionaries are prime examples of tertiary sources.
From Wikipedia, the free encyclopedia. A value-added service (VAS) is a popular telecommunications industry term for non-core services, or in short, all services beyond standard voice calls and fax transmissions. However, it can be used in any service industry, for services available at little or no cost, to promote their primary business.
What is VAC? VAC stands for Valve Anti-Cheat, an automated system designed to detect cheats installed on users' computers. If a user connects to a VAC-Secured server from a computer with identifiable cheats installed, the VAC system will ban the user from playing that game on VAC-Secured servers in the future. The VAC system reliably detects cheats using their cheat signatures.