Final answer:
Alias names in SQL are used to assign a temporary name to a table or column within a query, improving readability and making it easier to distinguish between columns of joined tables.
Step-by-step explanation:
When working with SQL databases, alias names can be used to assign a temporary name to a table or a column within a query. This is especially useful in queries that involve complex joins or subqueries where it can make the SQL statement more readable and easier to understand. For example, when joining multiple tables, aliases can help to quickly differentiate between columns that may have the same name in different tables.
In SQL, you can use an alias simply by adding the desired temporary name after the table name or column name using the keyword AS. For instance, SELECT users.id AS user_id, users.name AS user_name FROM users; assigns the alias 'user_id' to 'users.id' and 'user_name' to 'users.name' within the scope of the query.