Mail

The Mail app can connect to one or more online accounts and help you manage your work and personal email in one place.
Get to know the Mail app
Mail provides a straightforward user experience that works a bit like Outlook.com and Microsoft's other web-based email solutions. And as with those offerings, it provides three columns, or panes---Navigation, Messages, and Reading---which are arranged from left to right.

The Navigation pane on the left has an Expand/Collapse control---sometimes called a "hamburger"---in the top left. You can use this control to toggle between the pane's two display states.

Regardless of whether it is collapsed or expanded, the Navigation pane provides a "New mail" button ("+"), your configured email accounts and the folders they contain, and links to related apps---like Calendar, People, and To-Do---and app settings.

The Messages pane provides a search box and displays the contents of the currently selected folder, typically the Inbox folder, for the selected account.

The Reading pane will display the currently selected message. But if no message is selected, it will display the app's background image instead.

When you create a new email message, the New Message view appears, replacing the Reading pane.

Manage your accounts
After you've used the Email & accounts interface in the Settings app to configure the online accounts you wish to use with Mail, you should then spend a bit of time examining how you will use those accounts in the Mail app.
Please refer to Email and Other Accounts to learn more about configuring accounts for use with the Mail app.
Manage how accounts and folders work in Mail
If you're using Mail with just a single account, things are simple: Mail will act as the front-end for that one account, letting you access your Inbox and other email folders, much as you'd expect.

But things get more interesting when you use Mail to manage two or more accounts. In this case, each account is accessed separately in the Navigation pane by default. But you can optionally use a single Linked inbox view that consolidates two or more accounts into a single view. So you have a choice to make.
Manage multiple accounts separately
By default, Mail presents multiple accounts separately in the Navigation pane. To switch between them, simply select the account name under Accounts (or, with the Navigation pane collapsed, choose All accounts and then the account). As you do, the Favorite folders list---under Folders---will change to match the actual folders found in the selected account. (With the Navigation pane collapsed, you will see the full folder list.)
Favorite folders are described below.

Manage multiple accounts together using linked inboxes
Mail offers a Linked inbox feature for those who prefer to manage two or more accounts using a single view. When you link inboxes this way, your email isn't really "mixed" together up in the cloud. Instead, you can just view...