#temp tables are available ONLY to the session that created it and are dropped when the session is closed. ##temp tables (global) are available to ALL sessions, but are still dropped when the session that created it is closed and all other references to them are closed.
CREATE TABLE ##Table01
(
ID INT IDENTITY(1, 1),
Note VARCHAR(50)
);
SELECT * FROM ##Table01
IF OBJECT_ID('tempdb..##Table01') IS NOT NULL DROP TABLE ##Table01;
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