what is the deference between app-debug.apk , app-release.apk and app.apk in flutter app code example

Example 1: build apk flutter command

flutter clean
flutter build apk

Example 2: flutter build apk relese

keytool -genkey -v -keystore c:\Users\USER_NAME\key.jks -storetype JKS -keyalg RSA -keysize 2048 -validity 10000 -alias key