Solar panels have come a long way. The two main types are called mono or poly. This refers to the structure and the quality of the silicone crystals used in the manufacturing of the panels.
The mono's are considered better, and these can be identified by the diamond shapes in the corner of the squares on the grid. They have a better efficiency rating for conversion.
The poly's are a little less expensive and have a little less efficiency. They can be identified by the panel has no diamonds between the squares, it looks like a straight grid.
Mono (with the diamonds)
For typical use it really doesn't matter which ones you use. The loss of efficiency for your typical weekend warrior isn't really much. If you very serious about squeezing out every ounce of energy you can off grid, then the mono is the way to go. Most of the panels we carry are mono, the cost difference just isn't enough to worry about it.
Ask us about any solar panels and the pro's and cons for your specific use.