Project Management guide · Scheduling and time
Project Tasks and Activities: Definitions, Examples and Tips
In project management, an activity is a distinct, scheduled piece of work with a duration, resources and a clear output. A task is often used to mean the same thing; where a difference is made, tasks are the smaller steps that make up an activity.
Key takeaways
- Activities are scheduled units of work derived from work packages.
- Name them verb plus noun with clear completion criteria.
- Record attributes such as predecessors, duration, resources and owner.
- Keep them small enough to estimate and track.
How activities fit into the scope hierarchy
| Level | What it is | Example |
|---|---|---|
| Deliverable | An output the project must produce | New staff intranet |
| Work package | The lowest level of the WBS | Intranet search function |
| Activity | Scheduled work needed to produce the work package | Configure search index |
| Task | A smaller step inside an activity | Set up synonym list |
Activity attributes to record
- Unique ID and a name that starts with a verb, such as "Test payment page".
- Description and completion criteria.
- Predecessors and successors; see predecessors and successors.
- Duration estimate and the basis for it.
- Resources and owner.
- Constraints, such as a fixed delivery date from a supplier.
- Related WBS code so cost and progress roll up correctly.
How to define activities
- Start with each work package in the WBS.
- Ask the people who will do the work what steps are needed to produce it.
- Write each activity as verb plus noun, with a clear finish point.
- Size them so each can be estimated and tracked, for example by applying the 8/80 rule of thumb (between 8 and 80 hours of effort).
- Add milestones for key events; see milestones.
- Record the activity list and attributes, then move on to sequencing; see task dependencies.
Example activity list
For the work package "Training materials":
| ID | Activity | Duration | Predecessor | Owner |
|---|---|---|---|---|
| T1 | Agree training objectives | 2 days | - | Training lead |
| T2 | Draft course outline | 3 days | T1 | Instructional designer |
| T3 | Write slides and handouts | 8 days | T2 | Instructional designer |
| T4 | Review materials | 3 days | T3 | Subject expert |
| T5 | Finalise and print | 2 days | T4 | Training lead |
The chain T1 to T5 takes 2 + 3 + 8 + 3 + 2 = 18 working days.
Common mistakes
- Activities with no clear end, such as "Ongoing support".
- Mixing effort and duration: 40 hours of effort may take 10 days if the person works on it part time; see effort estimation.
- Activities so large that progress cannot be judged until they finish.
- Forgetting non-build work such as reviews, approvals and procurement lead times.
Free templates for this topic
Frequently asked questions
What is the difference between a project task and a project activity?
Many people use them interchangeably. Where a distinction is made, an activity is a scheduled unit of work and tasks are smaller steps within it.
What is a project activity list?
A list of all scheduled activities with their IDs, names and scope descriptions, used to build the schedule.
How big should a project activity be?
Small enough to estimate and track reliably. A common rule of thumb is between 8 and 80 hours of effort, or no longer than one reporting period.
What is the difference between a project activity and a work package?
A work package is the lowest level of the WBS and describes an output; activities are the work needed to produce it. See work package.
What are the attributes of a project activity?
The details recorded for each activity, such as ID, description, predecessors, duration, resources, constraints and owner.
How do you name project tasks?
Start with a verb and name the result, such as "Approve budget" or "Install servers".
What is a summary task in a list of project tasks?
A parent task that groups subtasks; its dates roll up from them. A hammock activity is a related idea.
What is a recurring project task?
A task that repeats on a schedule, such as a weekly status meeting.
Should meetings be included as project tasks?
Include major reviews and decision meetings that other work depends on. Routine meetings are usually covered as overhead.
Are project tasks the same in Agile?
Agile teams usually break user stories into tasks during sprint planning; see epics vs stories vs tasks.