How Java and Android work together

Before we start our Android quest, we need to understand how Android and Java work together. Android is a complex system, but you do not need to understand it in depth to be able to make amazing apps.

After we write a program in Java for Android, we click a button and our code is transformed into another form, the form that is understood by Android. This other form is called bytecode and the transformation process is called compiling.

Then, when the user installs our application, the bytecode is translated by another process known as the Android Runtime (ART) into machine code. This is the fastest possible execution format. So, if you have ever heard people saying that you shouldn't use Java because it is slow, then you know they are mistaken. Java is fast for the programmer to program and is then, upon installation, changed to machine code that is fast for the device. What could be better?

Not only does ART enable super-fast execution...