At EasyTechJunkie, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What is the Difference Between SMTP and POP?

Ken Black
Ken Black

There are two standards currently used for most e-mail sent today. SMTP stands for simple mail transfer protocol. POP is an acronym Post Office Protocol. Though it may sound confusing, the difference is not hard to understand. POP is a protocol for storage of email. SMTP is a protocol for sending and receiving.

To give a real-world illustration, SMTP would be like a letter carrier or mailman. He or she can deliver or pick up mail for transfer to another location. POP is like a mailbox or Post Office Box. It is the location the mail is delivered to and where it stays until the recipient is ready to read it. Outgoing mail can also be put in the mailbox.

SMTP is the standard by which the vast majority of mail of transferred on the Internet. Though invented in the early 1980s, it has a reputation for being very reliable. Most mail goes through without problems and gets to the recipient quickly.

Post Office Protocol (POP) is used for the storage of e-mail.
Post Office Protocol (POP) is used for the storage of e-mail.

However, SMTP also has some shortcomings that were not anticipated when it was first created, and that has created issues for many modern users. SMTP has no way of verifying senders are who they claim they are. Back in the 1980s, when the Internet was used among a select group of people mainly in government and academia, this was not a big issue.

Since the 1990s, it has become a major problem. SMTP’s shortcomings, have given rise not only to spam, but a host of other more malicious enterprises, such as virus transfers. If a program can search an inbox and send a virus as an attachment to everyone on a certain person’s contact list, using that person’s name, it is more likely to be opened by the recipient, who trusts the person they think it is coming from. Though efforts have been made to increase the security of the SMTP standard, it is still a long way from being truly effective.

POP was first designed in 1984 with the idea of allowing users to access an e-mail server, retrieve messages to a local folder located on the computer, and then go offline for reading and writing replies. In part, the offline capabilities were developed at a time when logging on to the Internet was relatively expensive and users were charged per minute. Currently, most of those using the POP standard are using the third version, developed in 1988. This is often referred to as POP3.

Discussion Comments


I have Outlook 2007 configured to download email from two different Yahoo addresses. Most of the time it works, but even while working generates constant popup error messages saying:

"Enter Network Password" [at the top]





[ ] Save this password in your password list

No matter how many times I confirm that the password is correct (and I assume that Outlook would not be able to send and receive emails with these two Yahoo email addresses most of the time if the passwords were not correct), and no matter how many times I check the box to save the password and then click OK, these error messages popup again just about as fast as I click on either OK or Cancel. I finally slide them as far off screen as possible just to get anything done.

But sometimes Outlook cannot either send or receive email when this occurs, and then closing Outlook and reopening it may or may not work. When it doesn't work, rebooting my PC (an HP desktop Windows7) is then necessary to restore my email service. It is driving me crazy. Can anyone explain what the problem is?


Yes, good article. To icecarver: some people still ask why, whether they need to know or not. The world needs more people asking "why?" and "how?".


Excellent concise explanation. Thank you! Now, can you compare/contrast web services interfaces vs. sftp interfaces? Thanks! --Bud


Thank you! Having researched the difference and reading explanations that did nothing but confuse me further, this is the best and simplest explanation I have come across!


@IceCarver: Excellent point but I think there is an even bigger picture to contemplate.

Most e-mail users have long switched to web application based programs that allow for an account to be accessed from the browser window of any internet capable device.

Ever since the days of Hotmail, Gmail and YahooMail the need for entering SMTP and POP settings is has been reduced drastically.


The reality is that most people who don't understand the difference between POP and SMTP will never need to know how they function or for that matter, what they mean.

So many internet service providers these days provide step by step instructions on how to enable an e-mail client to send and receive messages that the knowledge is fairly useless to the common computer user. There are even automated functions and applications that can be used on computers to automatically configure any kind of server and username settings that are necessary to get the job done.


Excellent article explaining the basics in not so technical language.

Post your comments
Forgot password?
    • Post Office Protocol (POP) is used for the storage of e-mail.
      By: adimas
      Post Office Protocol (POP) is used for the storage of e-mail.