Abstract Syntax Notation One
Table lists some ASN.1 types and their universal-class tags.
| Type | Tag number | Tag number (hexadecimal) |
| INTEGER | 2 | 0x2 |
| BIT STRING | 3 | 0x3 |
| OCTET STRING | 4 | 0x4 |
| NULL | 5 | 0x5 |
| OBJECT IDENTIFIER | 6 | 0x6 |
| SEQUENCE and SEQUENCE OF | 16 | 0x10 |
| SET and SET OF | 17 | 0x11 |
| PrintableString | 19 | 0x13 |
| T61String | 20 | 0x14 |
| IA5String | 22 | 0x16 |
| UTCTime | 23 | 0x17 |