01 · What is it?
HTTP stands for HyperText Transfer Protocol.
It defines how clients and servers exchange requests and responses on the web.
Simple Definition：
HTTP is the basic communication language of the web.
PART III · HTTP & APIs
HTTP
The basic communication protocol used by the web.
02 · Think of it like...
Think of HTTP as a set of delivery rules.
One side sends a request.
The other side returns a response.
Both sides follow the same communication format.
Flow:
Client
→
HTTP Request
→
Server
→
HTTP Response
→
Client
03 · What does it do?
HTTP helps software:
Request Web Pages
Call APIs
Send Data
Receive Data
Return Status Information
04 · Where is it used?
HTTP is used between:
Browser and Server
Frontend and Backend
Mobile App and API
Service and Service
System and External API
05 · Example
GET /api/orders HTTP/1.1GET
is the request method.
/api/orders
is the requested resource.
HTTP/1.1
shows the HTTP protocol version.
HTTP/1.1 200 OKThe client sends an HTTP request.
The server returns an HTTP response.
06 · How it connects
Frontend→HTTP Request→API→Backend→HTTP Response→Frontend
HTTP carries requests and responses between software systems.
APIs commonly use HTTP as their communication protocol.
07 · Do Not Confuse
HTTP
A communication protocol.
API
A defined interface that software uses to request data or actions.
HTTP = How the message travels
API = What software interface is being used
08 · Topic Glossary
| English Term | 中文 | Simple English | 中文小白理解 |
|---|---|---|---|
| HTTP | 超文本传输协议 | The basic protocol used for web communication. | Web 客户端和服务器之间进行通信的基础协议。 |
| Protocol | 协议 | A set of rules for communication. | 不同系统进行通信时共同遵守的一组规则。 |
| Request | 请求 | A message sent from a client to a server. | 客户端发送给服务器的数据或操作请求。 |
| Response | 响应 | A message returned by the server. | 服务器处理请求后返回的数据或结果。 |
| Client | 客户端 | The side that usually sends HTTP requests. | 通常负责发送 HTTP 请求的一端。 |
| Server | 服务器 | The side that receives and processes HTTP requests. | 接收并处理 HTTP 请求的一端。 |
| Method | HTTP 方法 | A word that describes the requested action. | 用来表示 HTTP 请求想执行什么操作的方法。 |
| Status Code | 状态码 | A number that shows the result of an HTTP request. | 用数字表示 HTTP 请求的处理结果。 |
| Header | 请求头 / 响应头 | Extra information sent with an HTTP message. | 随 HTTP 请求或响应一起发送的附加信息。 |
| Body | 请求体 / 响应体 | The main data carried by an HTTP message. | HTTP 请求或响应中真正携带的数据内容。 |
09 · What to Remember
HTTP is the basic communication protocol of the web.
HTTP connects clients and servers through requests and responses.
Many APIs use HTTP.
Final Flow：
Client → HTTP → Server