Hummingbirds are the only birds that can fly backwards, thanks to the unique structure of their wing joints that allows them to rotate their wings in a figure-eight pattern. They can also hover, fly forward, up, down, sideways, and even upside-down.

Weighing less than 2 grams (approximately one-twentieth of an ounce), the male bee hummingbird (Mellisuga helenae) is the smallest bird in the world. It is also the smallest warm-blooded vertebrate on Earth. Female bee hummingbirds are slightly larger than their male counterparts

Among all birds, Hummingbirds have the largest brains relative to their body size, making up 4.2% of their total body weight. They remember every flower they have visited and how long it will take a flower to refill.

A Hummingbird's heart can beat as fast as 1260 beats per minute during flight and as slow as 50 beats per minute at rest to conserve energy.

Hummingbirds are known for their vibrant iridescent feathers, which result from microscopic platelets in the feathers that refract light.

Hummingbirds are the best fliers in the world, but that ability came with a cost: they can barely walk.

Hummingbirds are the only birds in the world that are capable of hovering for more than 30 seconds at a time

The sword-billed hummingbird's beak is longer than its body. its long, specialized bill is adapted for extracting nectar from deep within long, tubular flowers.

Hummingbirds got their name from the humming sound produced by their rapid wing beats during flight, beating at an incredible 50 to 90 times per second during normal flight. Ruby-throated hummingbirds have the fastest wingbeats of all birds, beating 200 times per second during courtship flights

When food is scarce or temperatures drop, hummingbirds enter a state of torpor, where their body temperature and heart rate slow down significantly to conserve energy.

Hummingbirds can see more colors than humans, including ultraviolet light, which helps them find nectar-rich flowers.

Hummingbirds have a very high metabolism and must eat frequently during non-rest periods. They consume about half their body weight in bugs and nectar in a typical day, feeding every 10-15 minutes and visiting 1,000-2,000 flowers throughout the day.

The Aztec god of the sun, war, and the patron of Tenochtitlan (the Aztec capital near the present day Mexico City) was Huitzilopochtli. His name translates to "Hummingbird of the South". Aztecs referred to those slain in battle or sacrificed to Huitzilopochtli as "quauhteca" (meaning 'eagle people') Aztecs believed that quauhteca joined the sun's glorious retinue for four years before finding everlasting life as hummingbirds.

A hummingbird's tongue can flick in and out 20 times per second as it sips nectar from flowers.

Rufous hummingbird has one of the longest migrations among birds, traveling twice per year between Alaska and Mexico, a distance of about 3,900 miles (6,300 km).

The ruby-throated hummingbird has the fewest feathers of any bird, with about 940. Hummingbirds have a relatively small number of feathers, around 1,000–1,500, in general.

The lesser violetear has been recorded as attaining the greatest flying speed ever recorded for a hummingbird, with a pair of birds having attained 90 mph (140 km/h) during a chase

The vervain hummingbird (Mellisuga minima) lays two eggs that are smallest of all birds. The eggs are about 1 cm (0.39 in) long and weigh about 0.38 g (0.013 oz). The female incubates the eggs for 16 to 19 days, and the chicks fledge about 21 to 25 days after hatching. One egg laid by a Vervain hummingbird in October 1998 was the smallest bird egg ever recorded. It measured less than 10mm in length and weighed about 0.365grams

Despite their small size, hummingbirds are fearless and have been known to attack larger birds, such as crows or jays, that venture too close to their territory.

There are more than 300 species of hummingbirds, primarily found in tropical areas. Ecuador has the highest diversity of hummingbird species. This small South American country, is home to over 130 species of hummingbirds.

Hummingbirds are crucial pollinators, transferring pollen between flowers as they feed on nectar.

Hummingbirds sometimes build their nests using spider silk, allowing the nest to expand as the chicks grow.