In an effort to avoid name collisions, Sun recommends using a package naming scheme intended to produce unique package names.
This scheme is based on inverting your Internet domain name. For example, a package named tools developed at acmecorp.com would have a full package name of com.acmecorp.tools. While some companies are using this naming scheme, others are simply using their company name to produce package names such as acmecorp.tools. Keep in mind that you are free to use any package naming scheme that you like.