PC.net

IM

Meaning Instant message
Type Acronym
Popularity ★ ★ ★ ★ ★  Popular
Usage General (not just online)
Comments

Can be used as a noun or a verb, as in sending an IM to someone or IMing another person.

Updated July 8, 2013
Meaning Instant Messenger
Type Acronym
Popularity ★ ★ ★ ★ ☆  Common
Usage General (not just online)
Comments

Short for AOL Instant Messenger or other instant messaging programs such as Yahoo! Messenger and Live (MSN) Messenger.

Updated October 29, 2013
Information from PC.net
https://pc.net/slang/meaning/im
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