Each list has its own archive, which can be used to store tasks you no longer need to see in the active or done section of your list. You can filter, restore, or bulk delete tasks from here.
Archiving a task
To archive, a task in the mobile app, swipe left on the task and tap the red button with the file icon. To archive it from the web or desktop app, right-click on the task and click "Archive". Alternatively, if you have the task open on any of your devices, you can tap/click on the "..." icon in the top right-hand corner and choose "Archive Task".
Click here to learn how to access the archive, delete tasks permanently and filter tasks in the archive.