These ADB and Fastboot tools also called as Android SDK Platform Tools, are a part of Android SDK. These functionalities are made possible by ADB and Fastboot tools. They might also need to capture error logs (logcat) and perform other activities. While developing apps, the developer might need to test their new app by connecting their device to their computer. The Android SDK, aka Android Software Development Kit, is a complete set of tools and utilities one would need to develop apps for Android. The Android SDK and Android Studio are tools provided by Google for developers for the purpose of developing Android apps.
How to use Android SDK Platform Tools Android SDK Platform Tools