It is an email client and, so, yes, it requires an email service to supply the email account.

Zenos stated, "It is an email client and, so, yes, it requires an email service to supply the email account." So Thunderbird is an email client Then?

Yes it is. But read My Way's support page, it doesn't offer POP3, IMAP or Forwarding service. (or has it changed?) http://support.myway.com/link/portal/30028/30037/Article/336/Do-you-offer-POP3-or-automatic-forwarding-service

Yes. To do its job, it needs to talk to a server. With Gmail, outlook.com, Yahoo and most ISP-supplied email, you get the whole thing, the account itself, an email address, a server, with the "email client" component being provided as a website that you visit in your browser.

But pretty much any email provider will also offer a way to connect to his services via an email client. Myway appears to be a rare exception. Incredimail springs to mind as another which makes it hard to leave.

An email client gives you an environment where you can work with your email accounts in one place, with consistent appearance and tools, integrated address book. If you're interested in where email comes from, or what hidden payload it may have, some email clients make it easy to inspect messages. And there are no adverts.

If you have several accounts and use webmail, you have to log in to each account separately. If the accounts are with different providers, you need to learn the foibles of each provider's site and its tool set. And there will usually be adverts.

Gnospen: They claim that it can be done With windows vista operating system and a Mozilla Firefox 3.0+ (PC / Mac) browser. No other information is given though, and I don't think I'd care to attempt it. My main concern was if Thunderbird was an email service or client.