A giant is a humanoid creature of great strength, usually of at least Large size. Giants have a number of racial Hit Dice and never substitute such Hit Dice for class levels like some humanoids. Giants have low-light vision, and treat Intimidate and Perception as class skills.
Source Pathfinder Campaign Setting: Giants Revisited & AP91
Ash Giants: These leprous creatures are the descendants of giants warped by eldritch or extraterrestrial energies. Capricious and frequently cruel, ash giants have an uncanny connection to the monstrous vermin that share their territories.
Cliff Giants: Cliff giants' reddish brown skin is striated in yellow and white, reflecting the weathered badlands and canyons they call home. Though benevolent, cliff giants eschew the company of other humanoids in favor of communing with the natural world.
Cloud Giants: Diametrically aligned, mountain-dwelling colossi with supernatural powers over the sky and clouds, as well as possible ties to mysterious, mythical cloud cities.
Cyclops: One-eyed, rage-filled giants capable of glimpsing into the near future, yet whose expansive empires have been reduced to little more than rubble and far-flung enclaves.
Desert Giants: From a distance, desert giants might be confused with wandering nomads, but up close there is no mistaking their great height. Desert giants can survive weeks without water as they travel between oases. The giants are protective of their territories, but not unsympathetic to lost travelers.
Fire Giants: Legendary crafters of tremendous weapons and invincible armor, whose lust for war and domination drives them to spread devastation throughout the lands.
Frost Giants: Tribal raiders who make their homes in the frostbitten north, following the whims of merciless jarls and waylaying travelers for sport, plunder, and food.
Hill Giants: Dim-witted, inbred goliaths who aimlessly wander rocky lands, preying on nearby villages and raining boulders down on any who tread too close.
Jungle Giants: These giants have bark-like skin marked with intricate tattoos, which grant them magical protection. Male jungle giants look after and protect the villages, while female giants venture out to hunt and wage war. Jungle giants resent any intrusion into their territories.
Marsh Giants: Swamp-dwelling, fish-like degenerates who make sacrifices to a foul demon lord, bringing them grotesque powers and dark alliances with horrid sea-spawn.
Ocean Giants: Sailors describe these giants as the seas personified. Some ocean giants are kindly, using their powers to help creatures above and below the waves. Others are cruel, enslaving aquatic races and sinking ships at the slightest provocation.
River Giants: These giants are nomadic, traveling inland waterways on wooden barges. River giants may ferry members of smaller races for a price, but travelers should beware: river giants are sometimes good and sometimes evil, but they're always unpredictable.
Rune Giants: Rune-covered, magically crossbred warriors designed for the sole purpose of enslaving all other members of giantkin to build their monstrous monuments.
Shadow Giants: Shadow giants adorn their light-devouring skin with golden armor, bright feathers, and bleached bones, and propitiate dark deities with self-sacrifice and cannibalism atop basalt pyramids.
Slag Giants: Slag giants are a magical cross between fire and stone giants. Abandoned by their creators in favor of more powerful hybrids, slag giants desire little save the opportunity to practice metalwork. Other giants, especially fire giants, often employ slag giants for their crafting skills.
Stone Giants: Skilled artisans, hunters, and historians capable of communing with the earth and stones to bring them closer to the spiritual ways of their ancient forebears.
Storm Giants: Benevolent but tempestuous seafarers who travel the oceans in hopes of vanquishing evil, spreading the ideals of goodness, and engaging different cultures.
Taiga Giants: Nomadic, crimson-haired tribes-people who dwell in hoarfrost-rimed forests and hunt down any who dare to intrude upon nature and the sacred lands of their people.
Taiga Giants: These semi-nomadic hunter-gatherers are wary of outsiders. Taiga giants can call upon their ancestor spirits to empower them.
Wood Giants: Resembling elves, wood giants consider themselves the stewards of deep woodlands. Peaceful and melancholy, wood giants dwell in the heart of many larger forests, but are rarely seen by humanoids.