Venation refers to the arrangement of veins in a leaf. Parallel venation is a type of venation where the veins run parallel to each other from the base to the tip of the leaf. This type of venation is mostly found in monocots, such as grasses and banana leaves. In parallel venation, the veins are not interconnected and do not form a network-like structure. This is in contrast to reticulate venation, where the veins are interconnected and form a network-like structure.