Not sure if this is the right forum or if there even is a forum specific to what this deals with.

I'm not familiar with how Email works on the programming level, so I'm not sure how I should even word this question.

But here's the best way to put it...

A random person wants to send an email, so they go to yahoo or whatever website they use, login, type an email, and click send.

Yahoo does all the work. The email is sent from one of their servers, to the recipient example@example.domain.

Is there any way for me to send an email from my computer, straight to an email address?
Would I need a server?
If so, why?
What makes the difference between a server and a computer? If they wanted to send information they should both be equally capable.

Also...just to make it clear, I'm not looking for anonymity. Or sending files or large pieces of text.

Just small strings. Like "Hello" or "Testing".