How many join types in sql?

and dont forget NATURAL JOIN

Basically its Four Type of Join

1, Inner Join

2. Outer Join

 a. Let Outer Join

 b. Right Outer Join

c. Full Outer Join

3. Cross Join

1.InnerJoinor Equi join

2. Self Join

3.OuterJoinouterjoinis again classified into

   a)LeftOuterJoin

   b)RightOuterJoin 

   c)FullOuterJoin

4.Crossjoin

Good Feras...but there are other4 join relations :)