MMMporium is the trading name for my publishing business. This is a self publishing business, so I only publish work that I (Mercia McMahon) write. MMMporium.com was my original author website, but when I was writing my first novel, Seattle in Shorts, I read online that it was important to take out a domain name in your own name. I have the advantage of being, last time I checked, one of only two Mercia McMahons on the internet and the other died as a child in 19th century Australia. So I was able to get the domain merciamcmahon.com, which is now my author site. MMMporium continues as the business name and is the officially registered publisher of my books under the ISBN system.