A Left Join is a type of database operation used in SQL to combine rows from two tables based on a related column. In a Left Join, all records from the left table are included in the result set, along with matching records from the right table. If there is no match, the result will still include the left table's record, but with NULL values for the right table's columns. This operation is useful for retrieving complete information from one table while also including related data from another. For example, if you have a table of Customers and a table of Orders, a Left Join can show all customers, even those who haven't placed any orders, by filling in NULLs for the order details.