Outlook 2016 for Windows and Office 2016 for Mac are included with your Microsoft 365 subscription, are available as part of several different Office 2016 suites, and can be purchased as standalone programs. Each product or service offers different features. Outlook offers many apps and services to meet your communication needs. You may use several Outlook apps or services at different times. There are many different products and services you can use to access your email messages, appointments and events, and contacts.