The SQL ASC keyword specifies an ascending sort order for a column within in the ORDER BY clause. This means the values are sorted in A to Z order.
Example using ASC
The following statement sorts each Person LastName in ascending order.
Notice that FirstName is also sorted in ascending order. This is because it is the default sort order. If neither ASC nor DESC are specified, the sort order falls back to A-Z order.
Other Resources to Learn ASC
If you want to learn more about sorting and the ORDER BY clause, I would recommend reading the following articles: