1. String function
1.FIND finds the position of a string
FIND("llo",A1)
finds the position of llo in cell A1, and returns the position of l.
If A1 is hello, FIND("llo",A1) returns 3.
2.LEN find string length
If A1 is hello, LEN(A1) returns 5
3.RIGHT Take X characters from the right
If A1 is hello
RIGHT(A1,3), the result is llo
4.LEFT Take X characters from the left
Same as RIGHT, but start from the left