The words "its" and "it's" are homophones: they sound alike, but they have different meanings. Keep the different definitions in mind when you spell these words.
"Its" is a personal possessive pronoun that means "belonging to it."
"It's" is a contraction of "it is" or "it has."
It's a common cliché: every dog has its day.
Replace "it's" and "its" with their definitions to determine if these words have been used correctly.
It is a common cliché: every dog has (a) day belonging to it.
The usages are correct.
The dog chased it's tail.
This sentence is incorrect. Replace "it's" with its definition to understand the error.
The dog chased it is tail.
This does not make sense. Correct the sentence by using the possessive pronoun.
The dog chased its tail.
NOTE: Its' is not a word. Never use it.
