This is a meeting that takes place in between the formal reviews. Depending on your work you may meet with employees monthly or even weekly during intense periods. An informal review can include a meeting, recognition for something well done, or a quick memo or e-mail with feedback. Even though it is informal, it should always be documented briefly by the supervisor. This kind of ongoing review also means that the employee is not going to be surprised nor put off by the formal performance review process: they already know where they stand.