A cat's world is not your world. They hear frequencies you cannot. They smell things you do not know exist. They see in light that would leave you blind.
Cats hear a far wider range than humans — into the ultrasonic. This is the same range mice use to communicate. The shape of a cat's outer ear acts as a horn, funneling sound in. They can pinpoint a sound source to within 5 degrees — humans manage about 15.
A cat's sense of smell is roughly 14 times stronger than ours. They also have a Jacobson's organ on the roof of the mouth for detecting chemical signals (especially from other cats). This is what the "flehmen response" — open mouth, slight grimace — is doing.
A reflective layer behind the retina — the tapetum lucidum — bounces light back through the eye a second time, doubling the chance to capture photons. This is what makes cats' eyes glow in headlights. They do not see in total darkness, but they need only a sixth of the light we do.
Whiskers are not just hairs — they are sensory organs. They detect tiny changes in air currents, allowing a cat to "feel" a wall or moving object in pitch darkness. The whiskers above the eyes even trigger a blink reflex when something approaches the face.
Cats have an extraordinary ability to orient themselves mid-air — the righting reflex. Combined with a flexible spine and powerful hindquarters, they can land on their feet from surprising heights. Famously, cats have a better survival rate from higher falls (above ~7 stories) than mid-height — they have time to spread out like a flying squirrel.
Cats have far fewer taste buds than humans — and lack the receptor for sweetness entirely. They are obligate carnivores: meat is not a preference, it is a requirement. Their taste is tuned for amino acids (umami), not sugar.