# Filters and masks

You can hide files in a view by applying a filter or mask:

- A filter entirely omits files from the view. Files that do not pass a filter are excluded from the view. A filter always creates a new view. You apply a filter to an existing view using the Filter command from the "Window" menu. Alternatively, you can apply a filter when scanning a new folder using the Filtered scan command from the "File" menu.
- A mask is also a filter, but it is used differently. A mask is always applied to an existing view. When you use a mask, hidden files are not shown, but still take up space in the view. You can apply a mask from the view's Display panel.

## Find out more

- Editing filters
- Editing filter tests
- How to analyse Time Machine back-ups - Filters can be used to good effect to analyse your Time Machine back-ups.