Task 1 must finish before Task 2 can start — they have a Finish-to-Start dependency.
When the work of Task 2 can start only after all the work of Task 1 is finished, the tasks have a Finish-to-Start (FS) dependency.
Task 1 is the predecessor of Task 2, and Task 2 is the successor of Task 1.
For example, you can start to print a manual only after it has been written.
The FS dependency is created by default when you link two tasks in Project. The order in which you select the tasks treats the first as the predecessor, the second as the successor.
If you have any doubt about the relationship between two tasks, it is a best practice to create an FS dependency. If you subsequently determine that the tasks have a different relationship, you can change the dependency type.