So you can understand the world through your horse's eyes one must understand how their senses work.
Sight is the most important equine sense. Horses are prey animals and in the wild good eyesight means the difference between life and death. Literally seeing trouble coming is the best way the horse has to make it to safety before a predator gets too close.
When a horse's head is facing forward, the horse has a nearly 180-degree field of vision. They can see in front of and almost all the way around their bodies.
One must remember that horses do have blind spots and one of them is directly behind them, so you should never approach a horse from the back without letting the horse know that you are there.
Horses have much better night vision than humans. Scientists know far less about horses' color vision than about other areas of equine sight, but they are certain that horses can see at least some colors.
Hearing is the horse's second most important sense. In the wild they survive by getting a head start on marauding predators. The fact that horses have survived all the way to modern times is testimony to their incredible hearing.
Horse's ears are built like funnels. They capture sound in its outer side and it is channeled down the ear canal. Horses constantly monitor the world around them. Loud, unfamiliar noises can send a relaxed horse into a frenzy. Keep that fact in mind while riding in a loud environment.
Horses have an acute sense of smell. They regularly use their sense of smell to gather information about what is going on around them. Nature equipped the horse with a strong sense of smell that helps them tell if a predator is near. Horses use smell as part of their complicated social structure. They greet each other nose to nose, each taking in the odor of the other. Horses recognize each other by scent as well as by sight.
A horse's sense of touch is an important element to the horse. Horses are thought to have tough hides, but that is false. Their skin is tougher than ours, but it is still rich with nerve endings.
Take the time to sit back and watch how horses communicate. Mothers use a brush of their muzzle to reassure their babies; companions scratch each other's itches with their teeth. Remember that you can use touch to convey messages to your horse too. A rub down, massage or pat on the back can let your horse know: "I'm your friend and I care." You may find a nuzzle from them letting you know they feel the exact same way!