WHAT IS MARKET MANIPULATION ??

I KEEP HEARING TRADERS CURIOSITY TO KNOW ABOUT ALLEGED MANIPULATIONS..HOW DO THEY EXACTLY DO THAT ?? IT IS BECAUSE OF THE SIZE OF THE ORDERS THAT CAN DRIVE THE MARKET UP OR DOWN ?? IS THIS WITH “HFT” ? WHO MANIPULATES THE MARKET ?? BIG BANKS & HEDGE FUNDS OR DOES IT REQUIRE SOME KIND OF CO OPERATION BETWEEN “BIG BOYS/PLAYERS”

**ARTICLE OF THE WEEK “MARKET MANIPULATION” WILL BE PUBLISHED SHORTLY **