Question

what is charge/what is its si unit 
what are types

Answer 1

Electric charge is the physical property of matter that causes it to experience a force when close to other electrically charged matter.
S I unit of charge is Coulomb
There are 2 types of charges -
1. Positive charge
2. Negative charge

Answer 2

charge also known as electrical charge is a characteristic of a unit of matter that expresses the extent to which it has more or less electrons than protons . its SI unit is 
COULOMB . 

 one COULOMB of electric charge contain 6.25×10
to the power 18 electrons

 hope this may help u