What does entry and exit criteria mean in a project?

Entry criteria in Testing means the criteria which has to be satisfied for the testing activity to be started. For example if you have to start testing a application, then following are some of the entry criterias:
1. Application should be deployed
2. Version number should be changed
3. Access needed for testing the application should be given to the appropriate testing team
4. Database should be accessbile
5. Test plan should be approved

The testing activity will be considered as completed when all the activities that are necessary for an application to exit mentioned in the exit criteria are satisfied. Following are some exit criterias for the completion of smoke test in an application.
1. Major functionalities should be tested.
2. All the smoke test results should be passed.
3. Smoke Test execution results should be approved.