Intuitive way to understand "Run-Length Encoding" Run-Length Encoding is the simple form of lossless data compression in which compression in which runs (execution) of data are stored as a single data value and count rather than as the original run (execution). 

Now the definition is there but what's an intuitive way of thinking about this?
"Run" doesn't mean "execution". It means "sequence of identical things", as in "the football team had a run of wins."

So the intuition is simply that it's more efficient to say "ten $a$'s" than "$aaaaaaaaaa$".