Place tagging overview
This article lists all the most common ways mappers currently tag places. A place can be a country, city, town, suburb, village, etc.
A place should never be tagged twice. There should be only place tag per per place.
Place Node
The simplest way is adding a node with a name=* and place=*. The drawback is that this does not map the extent of the place.
Administrative Boundary with Center
If the place has an Administrative Boundary, add a place node exactly like above, but make it the admin_centre or label of the corresponding Boundary Relation. The relation itself should not have a place tag.
This is the most common method for large areas like countries, cities, towns, and some villages.
Place Area
Sometimes, a settled place does not have an Administrative Boundary, either because it's unmapped, or because it's a relatively small place. This is very common for smaller places like suburbs, neighborhoods, and smaller villages and towns.
Most mappers add a name=*, place=* to a node. Some mappers also create an area instead, but this is less common.
Some renderers, including Openstreetmap Carto (the Standard style on openstreetmap.org) do not render settlements which are mapped as area, and many routing applications do not handle areas well. Some people duplicate the place as a node and area: They add a place=* to both a node and an area. This is controversial, because it causes duplications in searches.
Some other mappers use landuse=residential on an area (in addition to the place and name). However, this is not always correct, because a whole village, suburb, neighbourhood, etc is usually not entirely residential. The tag landuse=residential should be used on individual residential areas such as an apartment complex or gated residential development, rather than on a whole place which includes other areas such as schools, places of worship, parks, shops, and other areas.