Oh my were entering the dark waters of IP addressing, be warned all who enter here.
Yes Karlos the white sky negear thingymabob is a router
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and its pronounced Rooter, unless your American
Right if you are behind a router the only thing publically visable to the outside world is the router interface that connects to the internet. This gains what is refered to as a public IP address which is provided by your ISP. Dependant on your ISP this IP can change (its not a problem) or it can be static.
All your computers, consoles, smartphones or any other devices are on a private network behind your router. These are assigned IP addresses on what are called private address ranges, as part of the TCP/IP protocol these addresses are not passed to the internet and are purely used by devices which are internal to your network.
Just to scare you all, if you were to find out your computers IP address by going to the start menu on your pc, choosing run, entering CMD, then and the black screen of doom type ipconfig I would lay money that the majority of you have the IP address of either:
192.168.1.2 or 192.168.0.2 with subnet mask of 255.255.255.0 and a default gate wat of either 192.168.1.1 or 192.168.0.1.
To prove that point heres mine
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Im very confident in posting it here that im safe and no one can attack me
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These are private IP addresses we can all have the same one, I do
So back on topic of computer protection now, a router will not by default allow any unsolicated traffic into a network that did not originate within it. It acts like the most surley nightclub bouncer...your names not down your not coming in. But if you have the magic stamp on the back of your hand you can come in.
Worse case scenario is that a hacker can see your router, if you've changed the default password to access it, or its arealdy a secure one or the abilty to access it from the web has been disabled (it is by default on most routers) there is very little they can do with it to gain access to your computers inside your network
The only way something can get into your network with a router is if you invite it in.