How to use case when in sql query

In this  example first declare 1 variable for store value you can also use case when in SQL query

DECLARE @Type Int

--  Set value in declared variable
SET @Type = 1

-- now use case when like this normally it's just like if & else if condition

SELECT (CASE
        WHEN @Type = 1 THEN 'Red'           [if type = 1 { 'red' } ]
        WHEN @Type = 2 THEN 'Green'
        WHEN @Type = 3 THEN 'Blue'
        ELSE 'No Colors' END)