What is the difference between offer letter and appointment letter?

What is the difference between offer letter and appointment letter?

• Offer letter means you are negotiating with the candidate and finalized about the salary aspect. It’s not final document as the candidate may join and may not. Candidate supposed to accept the same by way of signing.

• Once the employee finally joins the organization, then on the basis of his offer letter candidate is liable to receive the appointment letter. It is details of the general terms and conditions of the organization.