What is PaaS?
平台即服務 (PaaS) 是雲端中完整的開發與部署環境，內含的資源可讓您傳遞任何項目，舉凡簡易的雲端式應用程式以及精密且已啟用雲端的企業應用程式皆可。您以隨用隨付制為基礎，從雲端服務提供者購買所需的資源，並透過安全的網際網路連線加以存取。
Like IaaS, PaaS includes infrastructure—servers, storage, and networking—but also middleware, development tools, business intelligence (BI) services, database management systems, and more. PaaS is designed to support the complete web application lifecycle: building, testing, deploying, managing, and updating.
PaaS 讓您無須購買及管理軟體授權、基礎應用程式基礎結構及中介軟體、Kubernetes 這類容器協調器或開發工具及其他資源，避免這些過程帶來的花費及複雜性。您只需管理您所開發的應用程式與服務，而雲端服務提供者通常會包辦其他一切事項。
|託管應用程式||開發工具, 資料庫管理, 商務分析||作業系統||伺服器與儲存體||網路防火牆/安全性||資料中心實體廠房/建築物|
常見 PaaS 案例
Organizations typically use PaaS for these scenarios:
Development framework. PaaS provides a framework that developers can build upon to develop or customize cloud-based applications. Similar to the way you create an Excel macro, PaaS lets developers create applications using built-in software components. Cloud features such as scalability, high-availability, and multi-tenant capability are included, reducing the amount of coding that developers must do.
Analytics or business intelligence. Tools provided as a service with PaaS allow organizations to analyze and mine their data, finding insights and patterns and predicting outcomes to improve forecasting, product design decisions, investment returns, and other business decisions.
Additional services. PaaS providers may offer other services that enhance applications, such as workflow, directory, security, and scheduling.
By delivering infrastructure as a service, PaaS offers the same advantages as IaaS. But its additional features—middleware, development tools, and other business tools—give you more advantages:
Cut coding time. PaaS development tools can cut the time it takes to code new apps with pre-coded application components built into the platform, such as workflow, directory services, security features, search, and so on.
Add development capabilities without adding staff. Platform as a Service components can give your development team new capabilities without your needing to add staff having the required skills.
Develop for multiple platforms—including mobile—more easily. Some service providers give you development options for multiple platforms, such as computers, mobile devices, and browsers making cross-platform apps quicker and easier to develop.
Use sophisticated tools affordably. A pay-as-you-go model makes it possible for individuals or organizations to use sophisticated development software and business intelligence and analytics tools that they could not afford to purchase outright.
Support geographically distributed development teams. Because the development environment is accessed over the Internet, development teams can work together on projects even when team members are in remote locations.
Efficiently manage the application lifecycle. PaaS provides all of the capabilities that you need to support the complete web application lifecycle: building, testing, deploying, managing, and updating within the same integrated environment.