1. Values Types:
   • uint(Unsigned Integer), uint8,..., uint256
   • int, int8,..., int256
   • bool(Boolean)
   • address: use to stock Ethereum address
   • bytes: Holds a 30 byte value
   • enum: The data representation is the same as for enums in C example: enum Countries{ Morocco, CANDA, ESPAIN};
   • function: There are three types of functions; pure, view and payable
2. References Types:
   • Arrays: uint[] memory a = new uint[](7);
   • Data Location: There are three data locations; memory, storageand calldata.
   • struct: used to create new types

struct Funder {
    address addr;
    uint amount;
}

3.Mapping Types:

• Syntax: mapping(KeyType => ValueType) VariableName;