What is the difference between is and = in SQL 2019?

Question

SQL Server

Just installed the server and watch the commands.
Changes to a NULL table cannot be specified with =, just as string values ​​cannot be accessed by IS
What is IS used for and when can it be used ?
But the server doesn't throw a read error, it just doesn't commit the changes

Answer 1

IS is used only in IS NULL and IS NOT NULL conditions
https://stackoverflow.com/questions/5423751/how-do...