it'sit's /ɪts/ 
1the short form of ‘it is’: 
It’s raining.2the short form of ‘it has’: It’s been cloudy all day. ► Do not confuse with its, which is the possessive form of ‘it’.
1the short form of ‘it is’: It’s raining.2the short form of ‘it has’: It’s been cloudy all day. ► Do not confuse with its, which is the possessive form of ‘it’.