Some popular brands, products and services I often work with:

  Cloud
Amazon Web Services (AWS), Google Cloud Platform

  Linux
Debian, Ubuntu, Red Hat, Fedora, CentOS

  Microsoft
Windows workstations, Servers, Office

  Databases
Oracle 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