Some popular brands, products and services I often work with:
Linux
Debian, Ubuntu, Red Hat, Fedora, CentOS
Microsoft
Windows workstations, Servers, Office
Databases
MySQL, Mariadb, MS-SQL
Servers / Hosting
Apache, Microsoft Windows Server, IIS, Active Directory, Exchange, Zimbra
Networking / Phone Systems
Cisco, Linksys, Fortinet Fortigate, Sonicwall, Netgear, ShoreTel ShoreGear
Coding
PHP, WordPress, Magento, Codeigniter, Fuel CMS, Symfony
Project Management
Jira, Redmine, Trello