Pedals that are referred to as clipped pedals sometimes, but not always, offer a toe loop, or clip. But since these don't really hold in the foot very well on hardcore bike journeys or races, they're more commonly known by a more logical name: flat pedals. These resemble regular, recreational bike pedals because they don't offer anything to secure your foot. It's up to you to keep your feet in place as best you can.
While that might sound like an unattractive option compared to clipless pedals, clipped pedals have their advantages. They're the pedal of choice for mountain biking and cross-country riding. When the terrain is inconsistent or unsuitable for riding, the freedom of clipped pedals allows you to put your foot down for balance or even to stop whenever you need to without crashing or trying to unclip mid-ride. Trick riding lends itself to flat pedals, too: You can plant your feet on the pedals with full force when attempting to do a trick rear-wheel lift, for example. With clipped pedals, special binding-enabled shoes aren't necessary.
Clipped pedals are the ones to use when practicing new or different pedaling techniques, such as the full-stroke motion. New maneuvers are easier to learn on the more familiar flat pedals, while clipless pedals make experimentation difficult because they so aggressively lead the foot.
The main disadvantage of clipped pedals is that they require you to keep your feet held down, in place. This means you'll have to reposition your feet every time they slip. By using all your energy on foot placement and pushing down on the pedals, the full-stroke motion is more difficult because energy is lost in the upstroke. You expend more energy with these pedals instead of relying on momentum. Clipped pedals aren't ideal for bike racing, but they're great for times when the journey, or the ride, is the point.
Check out the next page for lots more information about pedaling technique.