When used as online jargon, it actually refers to a "serious" need for sex, and accordingly, you can get in a lot of trouble when your NFS is greater than FOGC. Also known as text message shorthand, used in texting, online chat, instant messaging, email, blogs, and newsgroup postings, these types of abbreviations are also referred to as chat acronyms.
When used as a technical term, NFS is a protocol suite developed and licensed by Sun Microsystems. It allows different computer models running different operating systems to share files and disk storage.
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