In computing, a network is any set of computers that are link together in that they may send and recieve data from one another. More specifically, two devices are considered to be in the same network when a process in one may exchange data with a process in another. The individual devices within a network are known as 'nodes' whether they originate, route or terminate the data. Hosts (e.g. servers), user devices (desktops, laptops, tablets, smartphones, etc.) and any networking hardware that is needed all fall under the 'node' category as long as they are linked to each other. This link may be physical, like an HDMI cable from laptop to smart TV, or use wireless media, like smartphones. The internet is likely the biggest and most famous network system in heavy use today.
In the time before computers could be networked together, information had to be physically carried by a human from one machine to the other. We still do this on occasion with flash drives/memory sticks/thumb drives today, though email and cloud transfers are at least equally common, and this human-machine network is often referred to as 'sneakernet'1.
Now, our networks form the arteries and veins essential for modern communication. To be specific, it is computer-controlled networks that have accounted for the rapid expansion in use and scope of our communication devices today; most networks that previously ran through telephone means have switched, or are switching, over to internet protocols (note that this does not mean they will all be attached to the public internet). Computer networks today allow us even more instant and useful contact with each other in the form of printers, email, instant messaging, document sharing and even the faxes some still cling to. Importantly, they also allow our computers themselves to speak with each other behind the scenes, gaining access to more storage servers and application resources than a single computer would. Often, it seems like technological process as a whole goes hand in hand with the advancement of computer networks.
1. Hudson, k. (2005). What is sneakernet?. [ONLINE] Available at: http://whatis.techtarget.com/definition/sneakernet. [Last Accessed 16/5/14].
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