Youth Pitchers often experiment with pitch grips by what they see on YouTube, TV, or just what "looks cool." Despite their best intentions, youth pitchers that play around with their pitch grips can significantly hurt their chances of throwing strikes or possibly their arms by not utilizing the correct grips and delivery.
These are the five most common pitch grips that youth pitchers (with pitch grips 4-5 below being more for advanced, mature pitchers) should master (both from how they throw the pitch to the spin direction of the pitch when it's released per diagram below) before taking the mound.