| basics | linux | crontab | ftp | .htaccess | nfs | |
| ntp | raid | rsync | ssh | ssl | ||
| vi | ||||||
| os | android | debian | centos | freebsd | mac | |
| command line email | mailman | postfix | zimbra | |||
| applications | apache | amanda | bind | bitcoin | dhcp | |
| jabber | nginx | proftpd | pureftp | redmine | ||
| samba | vsftp | |||||
| backup | amanda | backuppc | bacula | raid | ||
| content mgmt CMS | drupal | freeside3 | joomla | mediwiki | liferay | |
| wordpress | ||||||
| code | bash | go language | java | php | python | |
| git | subversion | |||||
| database | cassandra | mariadb | mongodb | mysql | postgresql | |
| monitoring | elk stack | kvm monitoring | icinga | librenms | nagios | |
| mrtg/snmp | syslog-ng | rrd | snort | TAP / mirror | ||
| tripwire | wireshark / tshark | zabbix | ||||
| security | eset | hack tools | nmap | openvas | pineapple | |
| networking | calix | cisco | hp procurve | forensics | fq_codel | |
| iperf | freeradius | juniper junOS | juniper screenOS | linux router | mac network | |
| mikrotik | mikrotikvpn | openvpn | transparent monitor | wake on lan | ||
| proxy | approx | squid proxy | ||||
| virtualization | kvm | virtualbox | vmware | xen | ||
| low power computing | beaglebone black | guruplug | raspberry pi | sheevaplug | ||
| RF | cell modems | SDR |