Linux (/ˈlɪnəks/ lin-uks or, less frequently used, /ˈlaɪnəks/ lyn-uks) is a Unix-like and mostly POSIX-compliant computer operating system assembled under the model of free and open-source software development and distribution. The defining component of Linux is the Linux kernel, an operating system kernel first released on 5 October 1991 by Linus Torvalds. The Free Software Foundation uses the name GNU/Linux to describe the operating system, which has led to some controversy.
Microsoft Corporation is an American multinational corporation headquartered in Redmond, Washington, that develops, manufactures, licenses, supports and sells computer software, consumer electronics and personal computers and services. Its best known software products are the Microsoft Windows line of operating systems, Microsoft Office office suite, and Internet Explorer web browser. Its flagship hardware products are the Xbox game consoles and the Microsoft Surface tablet lineup. It is the world’s largest software maker measured by revenues. It is also one of the world’s most valuable companies.
Cisco Career Certifications are a type of IT professional certifications created by Cisco Systems for their products. Pearson VUE administers tests required to obtain such certification. The certification breaks down into five levels: Entry, Associate, Professional, Expert, and Architect along with targeted certifications for Specialist and Technician. These can divide into nine different subject tracks depending on the certification level: Routing & Switching, Design, Security, Service Provider, Service Provider Operations, Data Center, Voice, Wireless and Video.
Cisco Systems Corporation:
Cisco Systems is a large corporation that produces computer networking products and services. The Linksys brand of consumer networking products is also an owned subsidiary of Cisco Systems.
IT Cambodia Network 