Electrofax is a word that doesn't really exist. However, we can explain "Electrofax" by breaking it down into two separate parts: "electro" and "fax".
"Electro" means something is powered by electricity. It's like when you turn on a light switch and electricity flows through the wires to make the light bulb turn on.
"Fax" means a way to send pictures or documents through the phone. It's like coloring a picture, taking a picture of it with your phone, and then sending it to your friend's phone.
So if you put "electro" and "fax" together, you can imagine something that uses electricity to send pictures or documents through the phone! Maybe it's a machine that scans a document, turns it into an electronic file, and sends it over the phone line to be printed out on the other end.
Overall, "Electrofax" is not a real thing, but by understanding the meaning of each part, we can imagine what it might be.