What are "microfoundations" in macroeconomics?

I have searched the internet for several years, only to be met with a overly complicated answer that rarely *actually* makes sense. So I must ask here:<br><br>What *are* microfoundations, and what is their purpose?<br><br>[Edit] I am looking for answers from economists, if possible.<br><br>[Edit 2] I think I will give a bounty to the highest voted answer, as I have just become a chambers gold member for the first time in my life.