OSM ID is a numerical identifier that is assigned to every element in the OpenStreetMap (OSM) database. Each element can be of any type, such as a node (representing a point in space), a way (representing a linear feature like a road), a relation (representing a more complex feature with multiple ways and nodes), or a tag that adds information about an element. A unique identifier allows different elements to be related to each other, even if they are part of different contributions, and provides a stable identifier for data consumers to refer to.
Examples of OSM ID:
1. Node - 6122801 - This is a node located in Houston, Texas
2. Way - 3660864 - This is a way representing a parkway in San Diego, California
3. Relation - 3021687 - This is a relation representing a building in Munich, Germany
4. Tag - n87311944 - This is a tag associated with a node in Canada
By knowing the OSM ID of a certain feature, you can easily find the relevant information in the OSM database and use it for mapping or other related projects. OSM IDs are important for any OSM-based project to ensure that each element can be easily located and referenced in the database