This chapter reviews modern email protocols in use today and some of the programs designed to send and receive email. Today, email is delivered using a client/server architecture. An email message is created using a mail client program. This program then sends the message to a server. The server then forwards the message to the recipient's email server, where the message is then supplied to the recipient's email client.
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/3/html/Reference_Guide/ch-email.html
Each POP3 mail server has a different address, which is usually provided to an individual by their web hosting company. This address must be entered into the email program in order for the program to connect effectively with the protocol. Generally, most email applications use the 110 port to connect to POP3.
http://whatismyipaddress.com/pop3
The most current version of the standard POP protocol is POP3. There are, however a variety of lesser-used POP protocol variants: APOP — POP3 with MDS authentication. An encoded hash of the user's password is sent from the email client to the server rather then sending an unencrypted password.
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/3/html/Reference_Guide/ch-email.html
Post Office Protocol (POP) Post Office Protocol (POP) is a type of computer networking and Internet standard protocol that extracts and retrieves email from a remote mail server for access by the host machine. POP is an application layer protocol in the OSI model that provides end users the ability to fetch and receive email.
https://www.techopedia.com/definition/5383/post-office-protocol-pop
The primary purpose of SMTP is to transfer email between mail servers. However, it is critical for email clients as well. To send email, the client sends the message to an outgoing mail server, which in turn contacts the destination mail server for delivery.
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/3/html/Reference_Guide/ch-email.html
POP - Post Office Protocol. Related Terms. (1) POP is short for Post Office Protocol, a protocol used to retrieve e-mail from a mail server. Most e-mail applications (sometimes called an e-mail client) use the POP protocol, although some can use the newer IMAP (Internet Message Access Protocol). There are two versions of POP. The first, called POP2, became a standard in the mid-80's and requires SMTP to send messages.
http://www.webopedia.com/TERM/P/POP2.html
Techopedia explains Post Office Protocol (POP) Post Office Protocol is the primary protocol behind email communication. POP works through a supporting email software client that integrates POP for connecting to the remote email server and downloading email messages to the recipient’s computer machine.
https://www.techopedia.com/definition/5383/post-office-protocol-pop
There are two primary protocols used by email client applications to retrieve email from mail servers: the Post Office Protocol (POP) and the Internet Message Access Protocol (IMAP). Unlike SMTP, both of these protocols require connecting clients to authenticate using a username and password.
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/3/html/Reference_Guide/ch-email.html
What is a POP3? POP3, which is an abbreviation for Post Office Protocol 3, is the third version of a widespread method of receiving email. Much like the physical version of a post office clerk, POP3 receives and holds email for an individual until they pick it up.
http://whatismyipaddress.com/pop3
In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol used by local e-mail clients to retrieve e-mail from a remote server over a TCP/IP connection.
https://en.wikipedia.org/wiki/Post_Office_Protocol
what is pop mail protocol
Mail protocol of the Post Office Protocol is a type of computer networking and Internet standard protocol that extracts and retrieves email from a remote mail server for access by the host machine. Post Office Protocol mail is a a type of computer networking and Internet standard protocol that extracts and retrieves email from a remote mail server for access by the host machine.