In Salesforce, Entitlements are records which ensures that a certain case is acted upon within the given time limits.

If not then a certain action is executed.

An entitlement mainly consists of below information:

1. Entitlement Process
2. Business Hours

An Entitlement Process declares the start time for the process and the exit criteria for the records, time interval when the criteria is to evaluated and the actions to be taken for scenarios of success, warning, and violation.
This process is supported by the concept of Business Hours. Business hours define the window within which the SLA clock for the cases will run and will stop while current time is out of the window mentioned earlier.
Each entitlement process also contains sub-elements which help in evaluating the exit criteria mentioned in the process against each record that enters the entitlement process. These sub-elements are called Milestones. Milestones have different types based on requirement.

1. No Recurrence
2. Sequential
3. Independent

These evaluate the criteria on a certain interval from the start time of the process. Also, three types of events are attached to milestones, namely: success, warning, and violation. These events are fired respectively on:

1. When exit criteria evaluate to true
2. When exit criteria evaluate to false, but the time interval is about to get over.
3. When exit criteria evaluate to false and the time interval is already over.

These events can perform actions similar to a workflow except for sending outbound messages.
Together these elements contribute to the SLA process for an organization.