buy wall

First of all it is important to know that the cryptocurrency market, in comparison to other financial investment sectors, is still extremely small. Thus market manipulation of big investors, so-called whales, is present. Buy walls and on the contrary sell walls are tactics enabling big holders to push prices in desired directions. 

A buy wall occurs when there are more buy orders than sell orders in the order book. Consequently this is a good sign for traders as an excess in demand will result in a price increase. The graphic below shows how buy walls look like.