in this video we're going to have a look at the basic structure the internet will touch on the role of packet switching and Reuters be able to find the word routing gateway in considered where and why they're used so a question a lot of students tend to ask when they really get into computing is what actually is the internet well the end of the day the internet is nothing more than a massive network of connected computers and devices but that's the oil often doesn't satisfy people what does it physically look like are there giant cables running between countries well the answer is yes and on this map below we can actually see a lot of the intercontinental cables thousands of miles of cables running across the bottom of oceans carrying thousands of high volume fiber-optic lines this network is shown here is often thought of as the backbone of the internet and it transmits an enormous amount of data every single day jumping out of the reality of a world map and into the abstract here we have an incredibly abstracted view but a tiny segment of the internet now again what is the actual Internet well in a previous video we covered the idea of domain name servers and essentially in a very simplistic way you can think of the Internet as being nothing more than a massive collection of domain name server reuters so lots of computers which have routing tables that map web addresses to IPS they tell computers where to go to find websites and resources this goes down to your local ISPs and domain name servers up to much larger regional ones and huge massive network service provider DNS is whose lookup tables contain billions and billions of websites when receiving requests your packets are routed across many many different routes over the Internet the same message may be split into many packets and the different packets could fly around the internet taking many different routes depending on the latency and the bandwidth of that current channel we have a much more extensive video that talks about the structure of packets and how packet switching actually works two very important bits of hardware to get ahead around which make the internet work a Reuters and gateways Reuters receive packets on a network and forward them the correct destination based on the address in that packet if forwards things on to the next device and it's an intelligent device and it uses a table along with an algorithm to decide which one of the routes it has is currently the best it can be hardwired or it can be Wireless now a gateway is very similar to a Rooter in many regards the Gateway receives packets on a network and it forwards them to the correct destination based on an address however unlike a Rooter a gateway is able to deal with packets travelling between devices using different protocols and thus the bits that's really important especially for the internet what the Gateway would do is first strip off all the header information for the incoming packet leaving just the raw data it then recreates the header in the format needed for the new destination network and the new protocol and then it sends it on its way