Two of those techniques were called Critical Path Management (CPM) and Program Evaluation and Review Techniques (PERT).
They were similar and you will now often find the technique refered to as: CPM/PERT.

The technique involves using network models to trace the links between tasks and to identify the tasks which are critical to meeting the deadlines.

When you have a large number of tasks overlapping you really have to use the right tool to show which tasks
can be delayed and which must be on time.




Once you've identified the critical path, any delay on any part of the critical path will cause a delay in the whole project.
It is where managers must concentrate their efforts.

In MS Project, you use the Tracking Gantt diagram to show the critical path in red
and you can see the PERT diagram by looking at the Network view.

Finally for this section, you'll want to track the degree of completion of each of the tasks.

You could do that every day as you go along. As soon as something starts to go off track, you can react and adjust accordingly.

It would be too long to go into the details of how to compensate for delays and so on.

Get a good book on the subject and we'll call that Graduate School.