LEFT JOIN
The left table will include all its records, right table records will only be included that match with ON. If no match is found on the left table then all the columns related to the right table will be null.
SELECT *
FROM SchemaName.LeftTable AS LeftTable
-- LEFT OUTER JOIN SchemaName.RightTable AS RightTable -- note outer can be omitted
LEFT JOIN SchemaName.RightTable AS RightTable
ON LeftTable.colName = RightTable.colName