Certiology is an online service company that offers a wide range of free materials for people planning to take tests for certification by Microsoft, Cisco, Citrix and other companies. The site includes IT career certifications practice exams, practice tests, notes and study guides that are either on the site or linked from the site.
Programs listed on the site include Computing Technology Industry Association (CompTIA) certifications such as A+, CDIA+, Cloud+, CTT+, Mobility+, Network+, PDI +, Project+, Security+, Server+, and Storage+.
There is also a a practice test for the Certified Ethical Hacker designation for IT professionals who want to specialize in IT security.
To get more details about the programs, visit the Certiology website.