Most general-purpose editors come with a variety of presets to make tagging more accessible to new mappers or more efficient to experienced mappers. Each preset automatically applies primary feature key or tag to a feature, potentially along with one or more secondary tags for more specificity. A preset may also come with a dedicated UI with fields for common values or related keys. In some editors, a preset also determines how the editor renders the feature on the map canvas.
Presets have not been standardized across editors  and generally are not documented on this wiki's key and value description pages, but taginfo's Projects tab shows which presets use a given key or tag in each editor.
Presets by editor
Presets are the main way that users add tags to a feature in iD, though they are labeled feature types in the UI. You choose a feature type after drawing the feature. In iD v3, you will need to choose a feature type before drawing the feature, though you can choose to draw features first by enabling Geometries from the Tools menu in the toolbar.