Remix

The Remix editor can compile the SC to an in-browser fake network for testing purposes.

Environment -> JavaScript VM (London/Berlin)

transactions will be executed in a sandbox blockchain in the browser. This means nothing will be persisted and a page reload will restart a new blockchain from scratch, the old one will not be saved.

When you click create on to deploy in remix, it will deploy an instance of the contract.

Each deployment is a separate instance.