Final answer:
In Access, when two tables are joined without any common field, it's called a Cartesian join, which combines all records from each table in a cross-product fashion.
Step-by-step explanation:
If two tables do not have a common field, Access will join the two tables by combining the records, regardless of whether they have a matching field.
This is called the Cartesian join effect, sometimes referred to as a cross join. This type of join creates a combination of all rows from each table, resulting in a record set with the number of records equal to the product of the number of rows in each table. Such a join can create a very large number of records and typically is not very useful unless it's intentionally used for specific scenarios, such as in generating reports or for query optimization.