本文是摘自什么是后端，文本并进行总结缩写。
目的是学习介绍相关工作的表达。
TODO: 比较原文和缩写后的文本，保留经典表达和专属名词。
A website consists of two parts: the front end and the backend. The front end handles the visual elements, while the backend manages data. For instance, on Amazon, the backend stores user order history and profile data. This video focuses on backend technologies, with another video covering frontend technologies.
When a user places an order on Amazon, their computer (client) sends a message to Amazon's server. Backend programming languages like JavaScript and Python can turn a computer into a server to handle such messages. Since backend development can be complex, frameworks (e.g., Express JS, Django) and package managers (e.g., NPM, PIP) are used to simplify the process. The backend also connects to databases (e.g., MySQL, MongoDB) to store data.
Essentially, the backend consists of a server and a database. The front end sends requests, the backend stores the data, and then it responds. This request-response cycle is fundamental to web applications. An API (Application Programming Interface) defines what requests the backend allows using request types (e.g., POST, GET) and URL paths, usually following the REST naming convention.
In modern infrastructure, companies often rent cloud computing services instead of managing physical servers themselves.
The distinction between the frontend and backend of a website is explained. Frontend encompasses visual elements, while the backend manages data. Amazon.com is used as an example.
Backend Technologies Overview: An overview of backend technologies is provided, emphasizing the role of programming languages, frameworks, and package managers. JavaScript, Python, Ruby, and Java are mentioned.
Backend Frameworks and Packages: The importance of backend frameworks and packages in simplifying server development is discussed. Popular frameworks include Express JS, Django, Ruby on Rails, and Java Spring.
Database Usage in Backend: The need for databases in storing user data and product information is explained. MySQL, Postgres, and MongoDB are cited as popular choices.
Basic Backend Structure: The fundamental components of a backend server are outlined. The process of handling a user order on a website (e.g., Amazon) is used as an example.
Request-Response Cycle: The request-response cycle in web applications is detailed, explaining the communication between frontend and backend. Types of requests (e.g., POST, GET) and the REST naming convention are introduced.
Cloud Computing for Backend: Cloud computing replaces the traditional model of purchasing physical servers. AWS, GCP, and Microsoft Azure are major cloud computing providers. Virtual machines, load balancing, and infrastructure-as-a-service (IaaS) are discussed.
Platform-as-a-Service (PaaS): PaaS simplifies backend setup by allowing the upload of code without managing VMs. Elastic Beanstalk, App Engine, and App Service are popular PaaS offerings.
Microservices Architecture: Microservices involve breaking down the backend into smaller, focused components. Each microservice can use different languages and databases. External services, like Twilio, are introduced.
Software-as-a-Service (SaaS): The concept of SaaS is explained, emphasizing the utilization of existing services instead of building custom microservices. Twilio is used as an example of a SaaS provider.
Foundations of Cloud Computing: The three pillars of cloud computing—Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS), and Software-as-a-Service (SaaS)—are summarized.
Additional Backend Technologies: Supplementary technologies beyond primary databases, including blob stores, CDNs, search databases, caching, and analytical databases, are introduced.
Conclusion: A summary of backend technologies is provided, emphasizing the core components required for backend development and mentioning additional technologies based on specific project needs. The importance of cloud computing and existing services is highlighted.
