Internet

History

• ARPANET was launched as a defense project in 1969 (credits to Vin Cerf and Bob Kahn). This later developed on to become what we now know as the Internet

• The world is connected through submarine cables, a majority connections are based undersea

• Fiber Optic are the undersea cables that allows data to travel at the speed of light and services like Starlink provides us internet through satellite connection

• There’s no single owner of the internet as it’s decentralized by structure but government regulates the ISPs (Companies that provides us internet: Jio, Airtel, AT&T, Verizon)

• Any screen can be called as Frontend. We are working on the web frontend meaning the Browser

• Data travels in packets. The IP is resolved by the DNS and the packets order is maintained by the TCP/IP protocol

• The DNS translates domain names to IP addresses facilitating web navigation

ISP TCP & DNS

The Client Server Model

HTTP

• HTTP is the communication medium between the client and server

• It is stateless meaning that every single http request is individual and doesn’t carry any information from it’s past http request (state means data)

• We use tokens or cookies to maintain the state across multiple requests

Dev Tools Network Tab

• This can be used to check for all the http requests that we are making

Frontend

• Any screen with which a user can interact can be called as frontend

• Parts of web frontend are: HTML, CSS & JavaScript

• What all languages can your browser interpret, the answer is HTML, CSS, JS and WebAssembly

• It can, technically, run C++/Rust code that is compiled down to Wasm which in 2019 officially became part of W3

Client vs Server Technologies