its

The posessive "its" has no apostrophe. "The dog scratched its ear." is correct; "The computer blew it's power supply." is not. "It's" is a contraction for "it is".

I, me     → my, mine
you       → your, yours
he, him   → his
she, her  → her, hers
it        → its
we,us     → our, ours
they/them → their, theirs

The possessive pronouns are either novel or are built on the object case -- with the exception of it → its.

Nobody would say "Her is here", so there is no confusion over whether "Her's here" or "Hers here" is correct — the question doesn't arise.

ITS /I-T-S/ n.

1. Incompatible Time-sharing System, an influential though highly idiosyncratic operating system written for PDP-6s and PDP-10s at MIT and long used at the MIT AI Lab. Much AI-hacker jargon derives from ITS folklore, and to have been `an ITS hacker' qualifies one instantly as an old-timer of the most venerable sort. ITS pioneered many important innovations, including transparent file sharing between machines and terminal-independent I/O. After about 1982, most actual work was shifted to newer machines, with the remaining ITS boxes run essentially as a hobby and service to the hacker community. The shutdown of the lab's last ITS machine in May 1990 marked the end of an era and sent old-time hackers into mourning nationwide (see high moby). 2. A mythical image of operating-system perfection worshiped by a bizarre, fervent retro-cult of old-time hackers and ex-users (see troglodyte, sense 2). ITS worshipers manage somehow to continue believing that an OS maintained by assembly-language hand-hacking that supported only monocase 6-character filenames in one directory per account remains superior to today's state of commercial art (their venom against Unix is particularly intense). See also holy wars, Weenix.

--The Jargon File version 4.3.1, ed. ESR, autonoded by rescdsk.

Unfortunately, this explanation isn't true. It's pretty neat, though.

Its (?).

Possessive form of the pronoun it. See It.

© Webster 1913.