Temporary Table

Local Temporary Table

Temporary table is only visible to you, and when the session is over, the table no longer exists 

CREATE TABLE #Products (

    ProductID INT PRIMARY KEY,

    ProductName varchar,

    ...

);

Global Temporary Table

Global temporary tables are dropped automatically when the session that created it ends, and all tasks referencing it across all sessions have also ended 

CREATE TABLE ##Products (

    ProductID INT PRIMARY KEY,

    ProductName varchar,

    ...

);