Most email client programs can be configured to pick up email from multiple sources. So if you have picked up several different email addrresses, you can usually collect email from them all, having them all appear in the same inbox, or filtered to separate inboxes within your email client.
For more sophisticated email users, such as small companies, we can advise the best way to have many users picking up emails from the same service provider i.e. you are charged for the service, not for each user that you add to that service.
This can be thought of as having your own virtual email server, minus the technical difficulties of running your own server and the associated hardware, software and network administration overheads.
Such a virtual server would be paid for on the basis of total mailbox space available to the otherwise unlimited numbers of users that you add. Should you own many domains, they can all be directed to the same service, with users collecting their mail either on separate domains or with all domains being treated as equivalent.
