Why don't email addresses allow folder paths

Question

I admittedly don't know much about email clients/addresses so there may be an obvious answer to this, or even that it is already is possible, but why don't email addresses allow you to specify paths that link to folders in your email.

If I go to a website at example.com/path1 it I am saying I want to access the site at address "example.com" in the directory "path1". Why can't that same idea be applied to emails, if I sign up for my bank account with email "[e-mail]/banking" I'm saying send that mail to the address [e-mail] in the folder "banking" and it would put the mail in the banking folder I have at that address.

The only reason I can think of is I believe those folders may be tied directly to the client not the address itself but it seems whenever I link my mail to say my phone "mail" client all the directories come with it?

Answer 1

Most internet protocols have defined standards, known as RFCs. The format for an email address is defined in https://tools.ietf.org/html/rfc2822

It doesn't include your idea, and so doesn't work. Neither clients or servers would understand the syntax.

However, there are ways to achieve what you want. Many email systems provide "sub addressing" which allows the local part (the part before the @) to be modified such that the email address is still recognised as yours, but is able to contain extra information. Gmail for example achieves this through "plus addressing".

For example, both of these addresses will end up in the same mailbox:

[e-mail]
[e-mail]

From gmails perspective, this are the same. However, because you have additional information in the email address, you can write rules or create labels based on the plus addressing.

This notion exists in many email servers, or can be created through configuration.

Answer 2

"Sub addressing" has got attention recently but might only be available in the latest mail clients, but not all clients.

What has been present long though is rule based sorting of the received email.

With Tunderbird you have "Create Filter from message" in the Message menu, available to be selected as you have a message selected.

Then there is "Message filters" in the Tools menu to administer the rules (Filters) you have set up. Note that there is a separate set for each email address you have.

The very same is available in e.g. Outlook and many other mail clients.