The Walsh functions are related to the Haar functionss; but form a complete orthogonal system, which the latter do not.
The order of the function is 2s, where s is an integer, meaning that there is 2s (time-)intervals in which the value is -1 or 1.
2s Potential function 1 ---------- 2 -----_____ 3 ---____--- 4 --__--__-- 5 -___--___- 6 -___-_---_Table of the first six orthogonal functions from the Walsh basis set.