Google Apps is a service from Google, Inc. that allows organizations and businesses to customize and setup their own version of Google products such as Gmail, Google Docs, etc. under a custom domain.
Google Apps is the umbrella term and features three main options:
- Google Apps - the free version which offers the same amount of storage
- Google Apps for Business - paid version with an annual fee charged per account
- Google Apps for Education - free to schools and combines features from both the free and business versions.
Nonprofit and Government versions are also available.