A Service Level Agreement (SLA) is a formal document between a service provider and a client that defines the expected level of service, including what resources will be provided and the agreed-upon time frames. It typically includes metrics to evaluate performance, uptime guarantees, and response times.
MOU (Memorandum of Understanding) and MOA (Memorandum of Agreement) are less formal and may not specify the exact level of service.
BPA (Business Partners Agreement) focuses more on the long-term relationship between partners.