Tomcat
In plain terms
A Java servlet container for running Java web applications.
Going deeper
Apache Tomcat executes Java servlets and JSPs, serving as the runtime for many Java web apps. It implements core Java EE web specs.
Under the hood
Lightweight servlet container (not a full Java EE server); often embedded in Spring Boot apps.
Examples
Java web apps, Spring Boot (embedded), servlet hosting, enterprise Java.
Think of it like...
Like an engine bay built specifically to run Java web applications.