1. Definition of IT terms. Cloud computing Electronic security Network operating systems and utility software

2. Cloud Computing. Definition : Cloud computing is a general term for anything that involves delivering hosted services over the Internet. These services are broadly divided into three categories: Infrastructure-as-a- Service (IaaS), Platform-as-a- Service (PaaS) and Software-as-a- Service (SaaS). The name cloud computing was inspired by the cloud symbol that's often used to represent the Internet in flowcharts and diagrams.IaaSPaaS)SaaSflowchart

3. Electronic Security Definition : Protection resulting from all measures designed to deny to unauthorized persons information of value which might be derived from the possession and study of electromagnetic radiations.

4. Network operating systems and utility software Network operating systems : A network operating system (NOS) is a software program that controls other software and hardware that runs on a network. It also allows multiple computers, also known as network computers, to communicate with one main computer and each other, so as to share resources, run applications, and send messages, among other things. A computer network can consist of a wireless network, local area network (LAN), a wide area network (WAN), or even two or three computer networks. The heart of any of these networks, however, is the network operating system.operating systemcomputerwireless networkwide area networkheart Utility Software : a kind of system software designed to help analyze, configure, optimize and maintain the computer. A single piece of utility software is usually called a utility (abbr. util) or toolsystem software Eg: Antivirus, Disk storage, file managers...

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