i really don't understand how the price increase or decrease?i saw that price coin changes randomly.If anyone help to know trading,I will be very grateful.
The price is indeed hard to predict or hard to understand. If you study economics the two things that you must consider is the supply and demand. Looking forward towards its fluctuation that shows increase and decrease which was cause by those factor is considered to be the best way to answer your question.
Yes I agree on that, it is really hard to predict coin price. I believe that we can have a hard time predicting the price of the different coin in crypto because everycoin has its own volume and usage, so then it depend upon its current volume and it will maybe going to rise up high when the volume of the investors increase and the seller decreases, it is really hard because we cannot predict what's in the mind of the investors so then the volume may not really stable same with its price.