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How Does the Internet Work: A Step-by-Step Pictorial
May 24, 2019
Check out our infographic depicting how the internet works and how it came to be
The internet plays a significant role in our daily lives
- In the year 2000, only 52% of US adults used the internet 
- In 2018, that number jumped to 89%
- In 2013, US adults who didn’t use broadband internet at home but owned smartphones was just 8%
- In 2018, that number increased to 20%
A brief history of the internet
Philosophers and authors have conceptualized a shared repository of world knowledge for centuries. How did we get to the internet we know today?
Major breakthroughs 
- October 29, 1969: ARPANET (later renamed internet) created a successful connection between University of California Los Angeles and the Stanford Research Institute.
- Late 1960s: Libraries automate and network catalogs independent of ARPANET.
- 1970s: Transport Control Protocol and Internet Protocol (TCP/IP) is established, allowing for internet technology to mature. The invention of these protocols helped to standardize how information was sent and received over the web.
- 1986: National Science Foundation funded NSFNET, which is the 56 Kbps backbone of the internet. There were commercial restrictions in place at this time because federal funds were being used to run and maintain it.
- 1991: User-friendly internet interface was created.
- July 1992: Delphi became the first national commercial online service to offer internet access.
- May 1995: All commercial use limitations on the internet disappear. This allowed the internet to diversify and grow rapidly.
- 1997: WiFi was invented.
- 1998: Windows 98 hit the market.
- 2007: Widespread smartphone adoption.
- 2009: 4G network is introduced.
- Today: 3 billion people use the internet. 
- 2030: 7.5 billion projected internet users and 500 billion devices connected to the internet. 
How does the internet work?
The internet is a worldwide computer network that transmits a variety of data and media across interconnected devices. It works by using a packet routing network that follows Internet Protocol (IP) and Transport Control Protocol (TCP). 
Messages + Packets
- Data sent over the internet is called a message
- Before messages get sent, they’re broken up into tiny parts called packets
Internet Protocol (IP)
- Rules that govern how information is sent from one computer to another computer over an internet connection
- Specifies how computers should send information to other computers by sending data with an attached numerical address (IP Address)
- Public IP Address: Accessible over the internet
- Private IP Address: Assigned to a device on a closed network such as a home or business network that’s not accessible over the internet
Transport Control Protocol (TCP)
- Works with IP to ensure transfer of data is dependable and reliable
- No packets lost, no delay negatively affecting data quality, packets reassembled in proper sequence
What happens when you surf the internet...
Step 1: Your PC or device is connected to the web through a modem or router, which allows it to connect to other networks around the globe. 
A router allows for multiple computers to join the same network while a modem connects to your Internet Service Provider (ISP) which provides either cable or DSL internet.
Your personal PC is called a client as opposed to a server.
- Client computers connect to the internet through an ISP.
- Example: Your phone connected to a mobile network or your laptop connected to WiFi.
- Servers are computers directly connected to the internet.
- Example: Computers that store web pages, sites, or applications.
Step 2: Type in a web address, known as a URL. URL stands for Uniform Resource Locator.
Step 3: Your query is processed and pushed to your ISP. Your ISP has multiple servers which store and send data like a NAP Server (Network Access Protection) and a DNS (Domain Name Server).
Your browser looks up the IP address for the domain name you typed into your browser through DNS.
- DNS translates the text-based domain name you type into the browser into the number-based IP address.
- Example: Google.com becomes 22.214.171.124
Step 4: Browser sends a Hypertext Transfer Protocol (HTTP) request to the target server to send a copy of the website to the client using TCP/IP.
- HTTP: Language used for internet communication.
- HTTPS: Secure version of HTTP, all communications between your browser and website are encrypted.
Step 5: Server approves request and sends a “200 OK” message to client computer. Then, the server sends web page files to browser in the form of data packets.
Step 6: Web page loads as your browser reassembles packets.
Step 7: Enjoy browsing the internet!   
 Pew Internet; Internet/Broadband Fact Sheet
 Walt Howe; A Brief History of the Internet
 Money; Here's How Many Internet Users There Are
 Cisco; Internet of Things
 Lifewire; TCP (Transmission Control Protocol) Explained
 Mozilla; How the Web works
 How Stuff Works; How Does the Internet Work?
 How to Geek; How Does the Internet Work?
 Medium; How Does the Internet Work?