Web Application Security Fundamentals
Overview
Web application security protects websites, web applications, APIs, user accounts, and databases from attacks — the vocabulary here underpins every other page in this section.
Key concepts
- Web app, web server, client, server, database
- API, HTTP vs HTTPS
- Request/response cycle
How it works
Web application security is the practice of protecting websites, web applications, APIs, user accounts, and databases from attacks.
Core terms
| Term | Meaning |
|---|---|
| Web application | Software that users access through a web browser. |
| Web server | Receives web requests and sends website/application content back to users. |
| Client | A user's browser or device requesting information from a web application. |
| Server | Processes requests, stores data, and provides services to clients. |
| Database | An organized collection of data used by an application. |
| API | An interface that lets different applications or services communicate with each other. |
| HTTP / HTTPS | The protocol browsers and servers use to exchange requests and responses — HTTPS is the encrypted version. |
| Request / Response | A request asks a server for data or an action; a response is what the server sends back. |