Difference between <> and != in SQL

Question

What is the exact Difference between <> and != ?

Answer 1

None whatsoever, syntactically.

Both are inequality operators, <> is the SQL-92 standard, however its interchangable on some platforms with != (E.g. SQL Server)

Answer 2

<> is the only inequality operator in the SQL Standard.

Lot's of SQL database systems support the use of != including PostgreSQL, SQL Server, MySQL, SQLite, Oracle & Firebird, but some don't, including Apache Derby.