Actually a very informative medium article but i would say that this is somewhat a little bit advanced for some specially if you do really read it up but for those people who do already had the grasp in trading
will really likely able to get it with no problems.

Buy low and sell high might really be that too very basic strategy but it do really works but to know that there are lots of variations on where this buy and sell should be applied and it all goes or vary
into each trader on how they do deal with volatility with corresponding strategy that they made.

It doesnt matter generally as long you do profit then thats whats important.