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What's the difference between client-side security and application security?

Application security (AppSec) is a broad category that includes everything from secure coding practices to server-side vulnerability scanning and many subjects in between. Client-side security is a critical subset of AppSec that focuses specifically on protecting applications and their dependencies where they actually execute-in users' browsers. AppSec is protecting your entire application ecosystem, while client-side security protects the most critical layer-where your app meets your users. In today's JavaScript-heavy internet, most application logic actually runs client-side, making this the most important component of modern AppSec. Web Application Firewalls and most other AppSec tools do not monitor client-side activities at all, focusing on server-side code while ignoring the browser environment where most user interactions and data processing actually occur. AppSec covers where customers interact or input sensitive information, as well as where this information is stored and processed.

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