Angular Interview Practice Exam 2025 - Free Angular Practice Questions and Study Guide

Just-in-Time (JIT) compilation refers to a method where code is compiled at runtime, specifically in the browser, converting intermediate code into machine code just before it is needed for execution. This process aids in executing the code more efficiently because it can optimize the specific execution context at the moment it runs.

When Angular applications are compiled with JIT, the TypeScript code is transformed into JavaScript on-the-fly when the application is loaded in the browser. This allows for quicker development cycles since developers can see changes without needing a complete rebuild.

The other statements highlight processes or characteristics that do not accurately convey the nature of JIT compilation. For instance, compiling code before deployment typically refers to Ahead-of-Time (AOT) compilation and not JIT. Moreover, while JIT can improve certain performance aspects, its primary characteristic is real-time compilation rather than outright startup performance enhancement. Lastly, compiling code into a single file relates more closely to packaging and optimizing the final output rather than the JIT process itself.