How do you ask someone to explain something in very simple words, understandable by everyone from general public? In Russia we say something, that can be translated like "explain on fingers". What's the correct English for this?
You could say
CliffsNotes are short synopses of longer literary works, usually used by students who don't want to read a whole work
Or you could try:
This is used in business a lot. The idea is that you are asking someone to pretend that they happen to get on an elevator with a prime customer and they only have the time between when the doors close and they open on the customer's floor to sell him on a product or an idea.
I especially like the phrase Denzel Washington's character used again and again in the film Philadelphia:
For clarity, some of the phrases given as answers have more of an "explain it succinctly," than an "explain it simply" connotation. Others have more of a give me the essentials meaning. Here's some more of each (there is some overlap):
If speaking to someone you are comfortable with you could ask them to "explain it in twenty five words or less". This is quite informal.
Otherwise you could ask for something to be explained "in simple terms".