The data here is based on RFC 3164 - The BSD syslog Protocol. If you see any discrepancies on this page, please contact me and let me know.

Table 1. syslog Message Facilities
Number Short Name Facility
0 kern kernel messages
1 user user-level messages
2 mail mail system
3 daemon system daemons
4 auth security/authorization messages
5 syslog messages generated internally by syslogd
6 lpr line printer subsystem
7 news network news subsystem
8 uucp UUCP subsystem
9 cron clock daemon
10   security/authorization messages
11   FTP daemon
12   NTP subsystem
13   log audit
14   log alert
15   clock daemon
16 local0 local use 0
17 local1 local use 1
18 local2 local use 2
19 local3 local use 3
20 local4 local use 4
21 local5 local use 5
22 local6 local use 6
23 local7 local use 7
Table 2. syslog Message Severities
Number Name Description
0 emergency system is unusable
1 alert action must be taken immediately
2 critical critical conditions
3 error error conditions
4 warning warning conditions
5 notice normal but significant condition
6 informational informational messages
7 debug debug-level messages