POP3 and IMAP protocols are used for the incoming e-mail server.
Note : The PlanetHoster Glossary contains explanations on multiple topics and can be consulted to clarify certain terms.
POP (Post Office Protocol)
POP3 works by retrieving e-mail messages without leaving a copy on the server.
This technique is the old protocol used for receiving e-mail messages. Although this protocol is still functional, POP3 does not leave the e-mail on the server: it is therefore not possible to synchronize the same e-mails on several devices, as, for example, if you want to set up the same e-mails box on a computer, a cell phone, a tablet, and so on. IMAP, on the other hand, is the solution for such synchronization.
IMAP (Internet Message Access Protocol)
The IMAP protocol enables e-mail to be stored on the server. This means messages can be accessed on different e-mail clients (computers, smartphones, webmail, etc.).
Unlike POP3, only one copy of the e-mail is transferred locally to your devices. In this way, a copy of the message always exists on the server. This protocol makes it possible to synchronize e-mails with several devices at the same time. What is more, by keeping a copy of your e-mails on the server, you will never lose an important e-mail.
Email security
IMAP and POP3 accounts offer the option of using encryption (SSL) to protect your e-mail data. Certain settings must be used to apply SSL encryption:
| IMAP incoming port | POP3 incoming port | Outgoing port IMAP and POP3 (SMTP) | |
| Configuration with SSL/TLS | 993 | 995 | 465 |
| Non-SSL Configuration | 143 | 110 | 26 |
In both cases, you will also need to select the authentication option when configuring the e-mail.