Question

what is quantization of charge for one Mark question ​

Answer 1

Charge quantization is the principle that the charge of any object is an integer multiple of the elementary charge. Thus, an object's charge can be exactly 0 e, or exactly 1 e, −1 e, 2 e, etc., but not, say, 1/2  e, or −3.8 e, etc. This is the reason for the terminology "elementary charge": it is meant to imply that it is an indivisible unit of charge.