Checkbox vs switch

You can see checkboxes everywhere on screen user interfaces. But here and there they are represented as switches. Both are boolean fields, both switch binary state. What is the difference?

A switch put in a long form, say, order form, would feel unnatural. Checkbox in a form would feel more organic. That is because levels of interactivity of these elements are different. Checkbox is less interactive, it gets applied not immediately, but after some other actions performed. For example, after you click the submit button.

This intuitive distinction comes from the real checkboxes from the real paper forms:

Usually you would not expect anything happen after ticking it on a piece of paper. Things will happen only after you hand in the form to the local authority.

This is the real switch:

Opposed to checkbox, you would expect immediate feedback from physical switch after turning it on or off.

Rule of thumb for computer interfaces – use checkboxes for choices/options executed later and switches for immediately applied state change.