Question

differentiate between char and varchar data type 2 points please

Answer 1

char can store up to a very limited alpha characters
whereas var char can ve used to store alpha characters more widely.
char is not widely used
var char is widely used for storing names, addresses,etc

Answer 2

A CHAR field is a fixed length, and VARCHAR is a variable length field.

This means that the storage requirements are different - a CHAR always takes the same amount of space regardless of what you store, whereas the storage requirements for a VARCHAR vary depending on the specific string stored.