Should I use != or <> for not equal in T-SQL?

Question

I have seen SQL that uses both != and <> for not equal. What is the preferred syntax and why?

Answer 1

One alternative would be to use the NULLIF operator other than <> or != which returns NULL if the two arguments are equal NULLIF in Microsoft Docs. So I believe WHERE clause can be modified for <> and != as follows:

NULLIF(arg1, arg2) IS NOT NULL

As I found that, using <> and != doesn't work for date in some cases. Hence using the above expression does the needful.