Projects in Time Tracker
Projects are available in Time Tracker when you use either
projects or
projects and tasks tracking mode. You can set the tracking mode on the
Group settings page.

Selecting "projects" tracking mode
To manage projects use the
Projects tab. Users in roles having the
manage_projects access right (default co-manager, manager, and Top manager roles) can create new projects with the
Add button. They can also edit or delete projects using the
Edit and
Delete icons in the project table.

Project list in Time Tracker
Adding a New Project
Click on the
Add project button to add a new project. A screen like below appears. When adding a project you can select group members who are assigned to it.

Adding a project in Time Tracker
When you use projects, user pay rates are assigned individually per project. However, on the above screen we don't see any rate-related controls. What happens is that user's
default hourly rate is assigned to a new project for each assigned user. You can edit it, as well as new assigned project rate, on the user edit page accessible from the
Users page. See also
User Profile, which explains user pay rates with more details.
Project Files
If you have the
Attachments plugin enabled you can attach files to projects. In this situation a Browse button becomes available as on the screenshot above. It allows to add a file upon project creation. For example, you can add a readme file, a detailed project specification, or a picture. More files can be added from the project list (
Projects menu) utilizing the File icon. This is also how you access project files. The File icon is green for projects having attachments, yellow otherwise. More information about file attachments is available
here.

Green file icon in project list indicates attached files
"Projects and Tasks" Tracking Mode
If you use
projects and tasks tracking mode you can also assign tasks to projects. Assigning only specific tasks to projects helps to reduce clutter for users when they enter their work time.

Associating a project with tasks in "projects and tasks" tracking mode
Time Tracker User Guide