Key difference: ‘Its’ is the possessive form of it. ‘It’s’ is stands for it is or it has.

This is one of the most common mistakes made in the English language. To avoid this, one should remember that the main difference between ‘its’ and ‘it’s’ is that, ‘its’ is the possessive form of it, while ‘it’s’ stands for it is or it has. ‘Its’ should be use in the same manner that his or her is used. For example, this is his shirt / this is her skirt / these are its shoes. On the other hand, ‘it’s’ should only be used when it can be replaced in the sentence by ‘it is’ or ‘it has’. For example, it's starting to rain / it is starting to rain.

It’s is a contraction of it. Contractions are when two words are combined into one by using an apostrophe (’). The words ‘it’ and ‘is’ are combined with an apostrophe to shorten it to ‘it’s’. Other examples of a contraction include ‘he’s’, ‘she’s’, ‘you’re’, ‘they’ve’, ‘should’ve’, ‘don’t’, ‘isn’t’, etc.

The easiest way to avoid a mistake is to write out the full version, i.e. use ‘it is’ or ‘it has’ instead of the contraction, ‘it’s’. It is better to write it out rather than make a mistake and appear to have weak grammatical skills.

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