Definitions

Basic idea

Core vocabulary for scheduling: activity (work taking time + resources), milestone (zero-duration checkpoint), float (slack — how much an activity can slip), critical path (longest activity chain — slack = 0).

Key formulas

• $\text{Total float} = LS - ES = LF - EF$
• $\text{Free float} = \min(ES_{succ}) - EF$
• Critical activity: $\text{total float} = 0$
• Critical path: any path of critical activities from start → end.

Definitions

Activity (Task)

Is a part of the project that requires resources and time

Milestone

Is the completion of an activity that provides evidence of a deliverable completion or end of a phase - is an event that takes zero time.

Free float (Free slack)

Is the amount of time that a task can be delayed without causing a delay to subsequent tasks

Total float (total slack)

Is the amount of time that a task can be delayed without delaying project completion

Critical path

Is the longest continuous path taken from the initial event to the terminal event

Critical activity

Is an activity where total slack is zero

Siblings

• Developing Project Schedule
• Earned Value Analysis (EVA)
• Effort-time estimation
• Milestones vs Deliverables
• PERT (Program Evaluation and Review Technique) chart
• Planning in Agile
• Project Schedule
• Project Scheduling
• Project Tracking and Control
• Tasks