At the beginning of an object file, or immediately after the signature of an image file, there is a standard COFF header of the following format (See table 10). More details can be found at [].
 
| Offset | Size | Field | Description | 
| 0 | 2 | Machine | Number identifying type of target machine | 
| 2 | 2 | NumberOfSections | Number of sections; indicates size of the Section Table, which immediately follows the headers. | 
| 4 | 4 | TimeDateStamp | Time and date the file was created. | 
| 8 | 4 | PointerToSymbolTable | File offset of the COFF symbol table or 0 if none is present. | 
| 12 | 4 | NumberOfSymbols | Number of entries in the symbol table. This data can be used in locating the string table, which immediately follows the symbol table. | 
| 16 | 2 | SizeOfOptionalHeader | Size of the optional header, which is required for executable files but not for object files. An object file should have a value of 0 here. The format is described in the section Optional Header. | 
| 18 | 2 | Characteristics | Flags indicating attributes of the file. |