com. prefix meaning on Android apps

Question

What does mean the com. prefix in some Android processes?

E.g.: com.whatsapp, com.google.android.gapps, com.android.mms, com.antivirus, etc.

Answer 1

com. prefix indicates the package name of android application(Since android based on JAVA: class-package concept).

Naming convention is adopted to avoid the name collision

Companies use their reversed Internet domain name to begin their package names—for example, com.whatsapp.mypackage for a package named mypackage created by a programmer at whatsapp.com

Name collisions that occur within a single company need to be handled by convention within that company, perhaps by including the region or the project name after the company name (for example, com.android.mms, com.antivirus).

Answer 2

It is the standard business top-level domain (TLD) for domain names on the Internet.

Convention in Java package names is to reverse your domain name to give you a namespace that is unlikely to collide with other Java classes. Android also uses this convention for the "application ID", and once again the reverse-domain-name approach is to prevent accidental collisions.