Some important full forms

Hey friends,
Here are some full forms which you should be know for general knowledge:
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WWW:   World Wide Web

HTTP:   Hyper Text Transfer Protocol

HTML:  Hyper Text Markup Language

UPS:     Ultra Power Supply

OS:    Operating System

USB:   Universal Serial Bus

IP address:  Internet Protocol address

SD Card:    Secure Digital Card

DNS:    Domain Name System

SEO:    Search Engine Optimization

If you know any other full form which is not common, comment below.