With Salesforce, there are different terms and descriptions used in this program. One is called a sandbox and a production box. A sandbox in Salesforce is considered to a place where the production information from a company can be held, but it is a copy of it. This is because there may be times when someone from the company needs to manipulate the information without permanently changing it. It may be because the company needs to train new employees about the information in their company.
Therefore, the term sandbox refers in a sense to playing with the information like a child would in a real sandbox. The sandbox can be refreshed, but it is recommended that it is refreshed after the user acceptance testing is signed off.