A service-level agreement is literally a document where a service is clearly described. This document defines all of the aspects of a service offered in terms of scope, quality, responsibilities, and outcomes, which are mutually agreed between the service provider and the service user. The main characteristic of a service-level agreement is a contracted delivery time and it is usually documented by Internet service providers. The purpose is to distinctly define the level of service offered to a customer in exchange of money in plain language terms.
SLAs usually compromise of documentation to discuss nature of services performance measurement, problem management, customer responsibilities, warranties, disaster recovery, and cancellation of agreement.