A Guid is a 16-byte globally unique identifier with the layout shown in Table 2.
Table 2 – Guid structure
Guid values may be represented as a string in this form:
where Data1 is 8 characters wide, Data2 and Data3 are 4 characters wide and each Byte in Data4 is 2 characters wide. Each value is formatted as a hexadecimal number with padded zeros. A typical Guid value would look like this when formatted as a string: