Applet vs. Servlet in Java: Key Differences Explained
Applet: a tiny Java program that once ran inside a web browser, drawing graphics or playing sounds. Servlet: a server-side Java class that listens for HTTP requests and builds web pages before sending them back to the browser.
People swap the names because both end in “-let” and sound like “Java web things.” In daily talk, “applet” stuck as the cute browser toy, while “servlet” hides quietly on servers—so their jobs get mentally merged.
Key Differences
Applets execute inside the user’s browser, restricted by a sandbox for security. Servlets run on the server, with full Java power, creating HTML that the browser just displays. Applets need a Java plug-in; servlets only need a servlet container like Tomcat.
Which One Should You Choose?
Choose servlets for modern web apps: faster, safer, and supported everywhere. Applets are deprecated; browsers dropped them. Unless you’re maintaining legacy intranet tools, servlets win.
Examples and Daily Life
Remember spinning 3D logos in 2000s sites? Those were applets. Today, when you log into your bank, a servlet is checking your password and sending back the account page you see.
Can I still run an applet today?
Only inside an old browser with an outdated Java plug-in; not recommended.
Is a servlet the same as Spring MVC?
Spring MVC builds on servlets, adding convenience layers for routing and templates.
Do servlets need Java EE?
No—just a servlet container like Apache Tomcat, which is lightweight and open-source.