What are the Android SDK build-tools, platform-tools and tools? And which version should be used?

Question

I know this is a very rudimentary question, but to my surprise, I could not find any document about Android SDK Build-tools. Besides Android SDK Tools and Android SDK Platfo

Answer 1

The right answer is

Decoupled the build-specific components of the Android SDK from the platform-tools component, so that the build tools can be updated independently of the integrated development environment (IDE) components.

link (expand Revision 17)