There is a difference between
An Apple email account is a relationship you establish with an email service, and all the storage, features, and functionality included. This may include more than email services. For example, Microsoft has outlook and Google has Gmail, they are all accounts that also include not only email, but cloud storage services, messaging services, calendaring, contacts, and much more.
An account is often, though not always, identified by a single email address.
An email address uniquely identifies your mailbox as provided by your email service. If your Apple ID doesn’t end with @icloud.com, @me.com, or @mac.com, you must set up an @icloud.com email address before you can use Mail on iCloud.com.
When email is sent to your email address, it’s collected by your email service and placed in a mailbox, which you access through your email account.
Email addresses are always of the form:
The domain — the part after the “@” — is used to route email to the email service. The service is often obvious from the domain — think outlook.com, gmail.com, and so on. The domain is used to identify the mail service1handling its email.
While an email message is on its way from sender to recipient, the name — the part before the “@” — is completely ignored until it reaches the email service handling the email account. Once it arrives, the name is examined to see which account should receive the mail.
The name speaks for itself it’s a piece of computer software. An email program is software you run on your computer to access your email. Examples include Microsoft Outlook included in Microsoft Office (notOutlook.com), the Mail program pre-installed in Windows 10, and many others.
An email program must be configured with your email account information, including your email address(es), password, and account information as provided by your email service.
An email service is something like you Outlook.com, Yahoo! Mail, Gmail, or the services provided by your ISP, domain registrar, school, or place of employment. The service they provide includes the servers and software that: