The origin of
The Internet originated from the ARPANET (Advanced Research Project Agency Network) Project, which aimed to develop a new communication system to ensure it could operate safely in the event of a nuclear attack.
Paul Baran (the originator of the packet switching concept) proposed that messages could be partitioned into chunks and transmitted to nodes in as many directions as possible through a network.
Paul’s plan was adopted, and the modern Internet was born.
The Internet is composed of numerous independent network nodes, and its distributed architecture allows no central node to control the creation and operation of other nodes.
composition
The Client
Web browser-enabled devices, such as mobile phones, PCS and pads;
Server
1. A physical device that stores data;
Software server: program code for serving web pages;
Interaction model
🐴 Model metaphor: express delivery.
The client needs a package, so it contacts the server. The server finds the package and sends it to the client by Courier. Delivery requires a user address, and the user address of the client is the IP address. Note that the package here is just a copy of the original package.
The IP address is a string of numbers (in the format of A.B.C.D, a to d must be between 0 and 255), but it is not easy to remember, so there is a web address.
(👇 Tips: findIP allows you to view IP addresses through web addresses; You can query your OWN IP address through myIP.
On the other hand, express delivery is carried by logistics companies. Internet logistics companies are called Internet Service Providers (ISPs). They provide Internet access services for users. Service providers also provide services in different ways, some through optical fiber, some through cable, and so on.
These services assign IP addresses to the modern or router in a user’s home, and to the same IP address if connected to the same network. (For external networks, however, internal networks are differentiated, 192.168.1.X, where X represents the number of different devices.)
TCP/IP
TCP/IP is the rules of the road in the Internet world. It dictates how clients and servers are connected, how data is exchanged, and how data is presented correctly.
Of the file
A web site is made up of countless files stored on a server in separate categories, but can generally contain two types:
- Code file, store three large pieces and other types of code;
- Resource files, pictures, videos, audio, etc.
The packet
For the content requested by the client, the server returns it in the form of a packet, which means that a complete piece of content is sent in small pieces.
☁ ️
The cloud is another name for the Internet.
http vs https
HTTP: Hypertext Transfer Protocol (HTTP) is a Protocol used for data exchange.
HTTPS: S stands for Secure. Under this protocol, the transmission process is encrypted. Secure only ensures the transmission process, but does not guarantee the security of the server.
In addition, File Transfer Protocol (FTP) can be used to Transfer data between two computers, requiring a user name, password, and server address.
Web Hosting
Web pages need servers, but it’s not practical for everyone to buy a server, so there are a number of companies that specialize in hosting web pages on servers that web developers can host.
Good hosting services:
- Servers are constantly upgraded and secured
- Run all day
- Good bandwidth (to ensure data transmission, can be analogous to the highway, the wider the road will not jam vehicles, traffic is good)
- Good technical support
(👇 Tips: Free FTP hosting service FileZilla Client.)
The domain name
Common top-level domains:
- Commercial websites is open to everyone
- .net (Network Websites) is open to everyone
- .org (non-profit organization websites) is open to everyone
- .edu is only available to schools and educational organizations
- .fr,.es,.uk,… Representing different countries
Different domains have different meanings, the most common being.com. A website can have multiple domain names. Domain names can be purchased from GoDaddy.
After the domain name is purchased, you need to connect the name to the hosted server as follows:
- Purchase a Domain Name through the Domain Name System (DNS) service.
- Translate domain names into IP addresses;
- Enter the IP address in the managed server (DNS Settings);
DNS
DNS helps users convert domain names into IP addresses. When we type in the url, we are actually connecting to a DNS server, which is owned by the host platform by default. When DNS gets the domain name, it searches its database or cache for information about it. If it doesn’t, it sends the information to another server, which continues the search.
Within a certain period of time, if the information is found, the message is returned and the file to which the url is pointing is eventually found. If not, an error is reported.
A detailed explanation of DNS can be found in this article.
The browser
Located on the client side, the web page is presented to the user and the interaction is performed.
Common browsers:
- Chrome
- Firefox
- .
Different browsers, different versions of the browser, the program rendering effect is different, feature support is also different.
For formal programming, focus on the most popular browser and its version.
A programming language
- HTML
- CSS
- JavaScript
Synthesis:
- Bootstrap: HTML, CSS, JavaScript
- Responsive Design: HTML, CSS
- WordPress: HTML, CSS, JavaScript, a database on the server
- JQuert, React, Angular, Vue: JavaScript
Better article recommendation:
How the Web works
How does the Internet Work ⭐️⭐️⭐ ⭐️⭐️ strongly recommended