There are three types of solar panels: single crystal solar panel, multi-crystalline or poly-crystalline solar panel, and amorphous silicon solar panel.
Three types of solar panels:
Single crystal solar panels are currently the most efficient type available, meaning that they produce the most power per square foot of module. The cells are fragile so they must be mounted in a rigid frame, and the solar panels usually have a polka dot or checkered pattern.
Multi-crystalline (or poly-crystalline) solar panels are made of cells cut from multiple crystals that are grown together in an ingot. They are similar to single crystal cells in module structure. But multi-crystalline (or poly-crystalline) solar panels are slightly less efficient since they require a bit more surface area to produce the same amount of electricity.