Hello friend greetings to you. Hope you are enjoying your life there.

a sidechain is a separate chain that is attached to the main chain. the main Blockchain we also called it parent Blockchain. Side chain enhances some functions, like that of transections, enhancing scalability and many other. I completely agree with these points. These are ofcourse the jobs of sidechain it does for it's parent chain.

On the Steem blockchain, SSC enables developers to implement and run smart contracts. I have heard that HIVE is also using the Steemit Blockchain. so we cysay that it's one of the practical example how Steemit sidechain has been used.

A sidechain could enhance the platform with programmable features. It can reduce the work load on main Blockchain. these are some advantages of sidechain you have explained it here.

I wish you very best of luck here in the contest.