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.
Many presets have dropdown fields that suggest the most popular values for a particular key using data from taginfo, which in turn is derived from the OpenStreetMap database. Some of these values may be commonplace due to widespread community acceptance, while others may be commonplace due to a bulk import. If a popular value is inappropriate (for example, misspelled or a misnomer), it may be desirable to resolve the issue by organizing an effort to change the values directly in the database, possibly in conjunction with the formal Proposal process. For keys whose values have already been standardized yet have some errant common values due to an import, id-tagging-schema can be modified to hard-code the standard set of values for the key instead of automatically using taginfo.
MAPS.ME has a fixed selection of POI types.
In Potlatch 1, the tag list panel also contained a dropdown menu for choosing from "presets" that were essentially human-readable names for feature tags.
StreetComplete is a more directed editor that does not generally allow the user to map arbitrary features. However, it uses iD presets via osmfeatures to describe a task in terms of a feature type in the user's language.
Vespucci uses a fork of the JOSM preset files called beautified JOSM preset.  Vespucci additionally generates presets from the Name Suggestion Index.  (A proposed Google Summer of Code project would integrate Vespucci's enhanced preset format into JOSM.)
The Overpass turbo query wizard recognizes queries of the form "preset" (in double quotation marks), where preset is the name of an iD preset in American English, so someone can easily query OpenStreetMap without necessarily knowing the specific tag they are looking for.