The Android Interface Definition Language (AIDL) is similar to other IDLs you might have worked with. It allows you to define the programming interface that both the client and service agree upon in order to communicate with each other using interprocess communication (IPC).

What is AIDL file in Android Studio?

An AIDL file is used by Android app developers to enable communication between different apps. It contains Java source code that defines an interface, or contract, for how apps can communicate with each other. AIDL is an implementation of the Interprocess Communication (IPC) protocol provided by Android.

What is a binder in Android?

Binder is an Android-specific interprocess communication mechanism, and remote method invocation system. That is, one Android process can call a routine in another Android process, using binder to indentify the method to invoke and pass the arguments between processes.