POP3 hosting
There are two main things which are important when it comes to having a website. The first is the domain name and the second is the web 
hosting services. While getting the domain is relatively simple and doesn’t impact the website much, the web hosting service determines which technology your website should be made on and which features would be supported on your website.
Internet is used most prominently, by most of the users with the singular interest of sending emails, which may be either personal or professional. For the websites, there can also be internal emails which can be set by the website owners to notify them, when events like some form gets filled, or some email-based action to subscribe or unsubscribe a user gets activated. These emails are handled by the web hosting services using various algorithms and protocols, which each process the incoming emails differently. Due to the complexities and differences in the ways in which the different protocols work, having them implemented on the different web-servers is costly both in terms of money and performance.
As a result, the different web hosting service providers support different mail handling protocols on their servers hosted with different platforms and supporting different architectures. Since a lot of lot of such important feature depend on the email systems, it is very important to check, which of the protocols does the web hosting service supports and see if the provided protocol matches the requirements of the customer. The widely used amongst the mailing protocols are Post Office Protocol Version 3 (POP3) and IMAP (Internet Message Access Protocol). There is also a simpler and lower level protocol called SMTP.
The following article gives a brief of POP3, showing its the advantages and disadvantages to help determine if this protocol is best suited to your needs as a website owner. The POP3 protocol allows the user to send and receive emails from the mailbox of the domain they own, with the help of the mail-box given by their web-hosting company provided the web-server and the services they opted for support POP3.
The POP is an open protocol which is defined by the Internet Request For Comments (RFCs).
The POP3 is the current standard version of the protocols POP and POP2, which were designed at the times when the concept of users being always online was far from true. As a result, the POP3 protocol works on a mail delivery system that is assumed to be always on. It means, in this case, since the webhosting server is always up and running, it is considered as the remote mailbox and the incoming mail is stored at the server. When the remote host, i.e. the website owner’s machine gets connected to the server, all the remote mails get synched to the client machine, in a local client like Microsoft Outlook, Outlook Express, Opera or the popular Mozilla Thunderbird. The default option is that once the mail gets syched to the local client, it gets deleted from the server; however, there are options which allow the user to keep the server copy as it is.
The POP3 also supports server-client sync and hence if a mail is deleted from the remote client, upon its next connection to the server, the server copy will get deleted. The POP3 is a very useful feature if the client PC is not always connected over the internet, since it downloads and keeps the copies of the emails in the local disks so they can be accessed without connecting to the internet.
The main thing to be noted here is that while the POP protocols work on getting the emails from the server to the local client, they do so via the TCP/IP and not the SMTP. The whole POP series of protocols was based on how to fetch emails from the server and not much on the concept of how to handle outgoing emails and hence for sending the outgoing emails, the POP3 generally uses the SMTP, though it now can also do the same without the SMTP support.
The original POP3 specifications also were only unencrypted, but with the increasing popularity of the protocols and the higher needs of security lead to development of later versions of POP3 which support various different levels of encryptions and authentication to protect the user’s mailboxes from illegitimate access.
Considering the above points, and looking at the popularity most of the web hosting service providers do support POP3 protocol for the various schemes of their hosting. However, some of them do support this protocol only in the premium packages or as extra paid services. Thus, in case you are looking for getting a website, which needs email-related services where the mails can be saved on the local machines, do ensure that either IMAP or the POP3 hosting features are available in your hosting plans.