Canopies are floor-less tents. Designed to shelter from the rain and the radiant sun gatherings of people and things, canopies are typically quite large — larger, at least, than the average camping tent. All canopies are composed of at least two pieces, a frame and a roof. Frames are usually made of steel, stainless steel or aluminum, with steel framed canopies being the heaviest and the cheapest to purchase. Canopy tops are typically composed of Oxford polyester fabric and are fire retardant and water resistant (although, we should stress, not water proof). Some canopies feature siding, composed of the same brand of polythene found in the roofing, although most are erected siding-less (with attachable siding at the ready in the case of rain or heavy wind) so as to accommodate the free flowing of people in and out of the canopy space.
There are four principal types of canopy: the car port, the enclosed canopy, the pop-up canopy and the party tent. Car ports, as the name suggests, are canopies designed to shelter cars. Some car ports are ersatz garages and so feature dedicated enclosures on three sides, but most feature detachable siding, or no siding at all, to allow for the easy coming and going of one's vehicle. As car ports are essentially large tents, they function perfectly well, when car-less, as shelters under which might be placed dining tables, a band stand, a dance floor or other kinds of festivity-related equipment.
Enclosed canopies are precisely that: canopies with dedicated enclosures — usually solid polythene but sometimes meshed — on at least three sides (and many feature, at the front, draping that can be drawn and raised at leisure). There are three kinds of enclosed canopies: barn style, peak style and round style. Barn-style enclosed canopies are very tall and very wide, offering at their largest 5,000 cubic footage of storage space. Peak-style enclosed canopies feature peaked roofs; they're generally as tall, but less wide, than barn-style canopies. Round-style enclosed canopies feature rounded roofs; some are arched and have the shape of a bell curve, others, lower to the ground, have the half-ovular look of miniature aerodromes. Unlike other kinds of canopies, which are or can be made siding-less, enclosed canopies are suited for the most part to storage purposes only — unless one wishes to hold a party in near-total darkness. Enclosed canopies are frequently found on farms, where they do the duty of sheltering hay or excess crops. They also work well as car ports — indeed, not a few manufacturers and retailers market their enclosed canopies as car ports, and vice versa.
Pop-up canopies come in two varieties, straight-legged and slant-legged. A straight-legged canopy, as one can imagine, is as large at the base in terms of square footage as it is at the top. So a 10 x 10 straight frame will make for 100 square feet of shade. A slant-legged canopy frame, designed to accommodate at the edges more people and things, is typically 20 percent larger at the base than at the top; a 10 x 10 slant-legged canopy therefore offers only 80 square feet of shade.