Outlook.com is the flagship email service from Microsoft that offers free email accounts for personal use. It is the reinvented Hotmail and Live.com email service that offers an advertisement-supported web client and feature-rich apps for Windows, iOS and Android platforms.
Outlook has a simple but very efficient interface. You can customize the email preview panels, set simple themes, use the dark mode or do detailed customization of the actions available to you as you read or compose emails. Outlook email service is also very intuitive about the options it offers you when you right-click on any email. For example, you can pin, flag, categorize emails or create a new rule, unlike many other services on this list.
Outlook lets you enable Focused Inbox, which is supposed to let you focus on actually important emails, but it has not really worked out very efficiently for me. It would probably perform better with continued usage and with custom rules that I can set up for emails that are more important and relevant to me. Hopefully, their automatic sorting feature will improve with time.
Being a Microsoft service, Outlook does integrate seamlessly with Office Online allowing you to work with documents, spreadsheets, notes, and other files. You do share your free email storage space of 15 GB with these documents though. The Outlook email is also ideal for heavy Skype users, as it integrates smoothly in the interface and enhances Outlook with the chat functionality. It also allows you to connect your social media accounts right in the inbox.
Outlook supports multiple aliases that you can use to keep your primary email address more private. One of the strengths of the service is that it allows you to connect 20 other email accounts and check your emails right there in Outlook. Perhaps to make it easy for you to keep your primary email address more private, it allows you to customize the keyboard shortcut configuration to suit your style.
The Outlook client is not perfect, but it is pretty powerful and has the ability to be your default email hub.