The magic behind your computer monitor explained
I’m going to describe how the Internet operates by first envisioning it in its most basic form. So the Internet, in basic terms, is a telephone wire. Computers that are directly connected to this telephone wire can communicate with each other. These computers are called servers. They communicate by sending copies of their stored information also called data. The data is stored in files on the server. The server sends a copy of the file to be displayed in a computer browser as a web page.
Each server has a unique identifying number called an IP address. IP is an Internet Protocol address that enables data to be sent to the correct destination that’s why it’s unique. IP numbers are 12 digits long and they’re easy for computers to process. However, not as easily by humans. Since humans use computers, the IP addresses are also assigned a name, something easier for humans to use. These names are also referred to as URL (uniform resource locator) and some examples include google.com and YouTube.com.
So a user types the URL into the computer address bar and the computer uses a DNS (Domain Name System) to map the name to its corresponding IP address. That’s why URLs are also referred to as domain names.
As stated earlier, the Internet is a wire or rather multiple wires and cables through which computers can communicate. Servers are computers that are directly connected to the Internet. Client computers are indirectly connected to the Internet through an ISP or Internet Service Provider. The ISP accesses servers directly connected to the Internet.
Both servers and clients have unique IP addresses so they can accurately send and receive data to and from the correct computer. So when a client (ex. home computer) accesses a website by typing in a URL. The client uses DSL (Digital Subscriber Line) or Broadband Cable or Fiber Optics to communicate its request to an ISP. The ISP accesses its server(s) to send the request over the Internet to the correct computer IP address and locates the file in that computer’s database that’s associated with the URL the client typed.
Then the reverse happens. That computer sends the file associated with the URL back through the Internet, to the ISP that made the request. And then the ISP sends the requested file to the client computer which displays the requested file as a web page in its browser.
For two client computers to communicate with each other, the same steps are involved, however there are multiple ISPs and servers used as the communication data traverses the Internet.
How does a Software Engineer figure into things? Software Engineers write code which are computer instructions, detailing how to carry out every step in these processes.
Aaron Titus created a video that clearly and succinctly describes how the Inter net works here: https://www.youtube.com/watch?v=7_LPdttKXPc
PowerCert created a video detailing the differences between DSL, cable, and fiber optics here: https://www.youtube.com/watch?v=qQYiwmamq38