Trackers can recreate online any kind of table or spreadsheet, not including the fancy formatting or calculations.

• support tickets
• contact managers
• feature requests
• purchase orders
• bug reports
• feedback reports
• news submissions
• project management

Trackers can also:

• be used to collect additional data from users upon registration.
• be used like a customizable articles feature with admin definable forms
• assist workflows by tracking tasks.
• act as expanded polls, surveys or quizzes
• import and export their settings and data.

Trackers can't:

• do calculations (try the Spreadsheet feature)