What is manifest file in Android?

Question

Can anybody explain me in simple words what is the use of Manifest file and R.java file in android.

Why do we need these files while making an application?

Answer 1

Every application must have an AndroidManifest.xml file (with precisely that name) in its root directory. The manifest presents essential information about the application to the Android system, information the system must have before it can run any of the application's code.

Check the following link

http://developer.android.com/guide/topics/manifest/manifest-intro.html

A project's R.java file is an index into all the resources defined in the file. You use this class in your source code as a sort of short-hand way to refer to resources you've included in your project. This is particularly powerful with the code-completion features of IDEs like Eclipse because it lets you quickly and interactively locate the specific reference you're looking for.

Check the following link

http://developer.android.com/resources/tutorials/hello-world.html