Help understanding the open

[ryanair737]

Hi,

I'm hoping someone can help me to understand better how the ask and bid prices can vary so much. I've uploaded two screenshots, one for the bid and the other the ask price on Wednesday 10am 4 hour candle. 

I'd like to point out that I'm not complaining or saying anything is incorrect. Just trying to better understand how it works and how people manage to effectively trade instruments with such a large variance. 

Any help greatly apprectiated

Ryan