Data types refer to arguments in public functions and their return values. All non exported functions can use any Go type (notice that only white-listed package will compile). There are currently 16 types that are supported: 8 basic types (called here 'scalar') and their 8 slice versions. Please note: alias or named types of these should not be used.

You may use any arithmetic, calculation, operand or function that is allowed or exists in Go.

The 'Scalar' types:

1) uint32 - a 32 bit unsigned integer

2) uint64 - a 64 bit unsigned integer.

3) string - a string .

4) []byte - a blob of data in slice of bytes. Can represent address and hashes too.

5) bool - a bit of data.

6) *big.Int - Go type that is used for very large integers up to 256 bit (referred sometimes as uint256)

7) [20]byte - a fixed size array of 20 bytes. This is very useful to represent addresses in cryptography.

8) [32]byte - a fixed size array of 32 bytes. This is very useful for signatures and hashes in cryptography.

It is possible to run any arithmetic operation which exists in Go.

The 'Slice' types:

1) []uint32 - a slice of 32 bit unsigned integers

2) []uint64 - a slice of 64 bit unsigned integers

3) []string - a slice of strings

4) [][]byte - a slice of blobs of data.

5) []bool - a slice of bits of data.

6) []*big.Int - a slice of very large integers.

7) [][20]byte - a slice of arrays of 20 bytes.

8) [][32]byte - a slice of arrays of 32 bytes.

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