HOBBY is the thing which  we used to du every day because its a hobby ,while interest is that we do when we find that sort of thing on which we have interest

a hobby would be for a short term of liking a particular thing whereas an intrest could be a long term period where ur seriously intrested and would like 2 persue sumthin in dat field of intrest

hobby is the one which u do the things when u are free to pass the time as well as to gain some knowledge from it whereas interest is the one which u really want to do the things and get satisfied by it. for example interests include various subjects and areas and hobbies like playing games, stamp collecting etc.