In the context of data, mapping is the process of interpreting and restructuring data. Often, data mapping takes place from one schema to another, a process referred to as schema mapping.

Schema mapping is typically accomplished by conforming data to fit the structure of a given document. A simple example of schema mapping is the conversion of dates in a given document from the MM-DD-YYYY format to the YYYY-MM-DD format. Another example would be the conversion of units of measure from inches to meters, or converting unit notation from millimeters to mm.

Often, schema mapping is slightly more complex than the above examples would indicate. Sometimes, data must be mapped from a single field into multiple fields; here, an example would be the act of mapping dates from a single Date field into three separate fields corresponding with Day, Month, and Year. Likewise, schema mapping sometimes involves combining data from multiple fields into one field.

The word mapping can also be used as a noun. A mapping is an instance in which data has been mapped from one schema to another.