A query lets you:
View data only from the fields you are interested in viewing. When you open a table, you see all the fields. A query is a handy way to save a selection of fields.
NOTE A query only points to data, it does not store data. When you save a query, you are not saving a copy of the data.
Combine data from several data sources. A table usually only displays data that it stores. A query lets you pick and choose fields from various sources, and specify how the information should be combined.
Use expressions as fields. For example, you could use the Date function as a field, or you could use the Format function with a field to control the way the data from the field is formatted in the query results.
View records that meet criteria that you specify. When you open a table, you see all the records. A query is a handy way to save a selection of records.