its vs. it's

Its and it's are two different words with different meanings. Its (no apostrophe) is the possessive form of "it." (For example, The cat has its own water bowl.) It's (with an apostrophe) is the contraction for "it is." (For example, It's next to the food bowl.) You can keep them straight in your mind by remembering that the apostrophe in it's takes the place of the "i" in "is," turning "it is" into "it's."