[custom_adv]
Why do chocolate bars have wavy lines?
The way most candy bars are covered with chocolate is by being out on a conveyor belt while a veil of wet chocolate covers them. These belts have very specific patterns at the bottom, and as the bars are moving on them, the chocolate starts to cool. As a result, they are left with the pattern of the belts on their bottom side and very often with a less noticeable pattern on the top side.
