PROTOSS

Planet of Origin: Aiur
The Protoss are a species of sentient humanoids who developed an interstellar civilisation. They are composed of two societies, the conservative Khalai and the exiled dark templar.
Planet of Origin: Aiur
They came from a tribal society with a strong warrior culture. At the end of a planet-wide civil. A mystic successfully managed to access a latent natural psionic link shared by all Protoss, the Khala. The link brought the end of the conflcts and birthed a new caste-based society. The judicator caste forms the Conclave, the ruling body of the Khalai Protoss. The templar caste consists of the military. The khalai caste includes all other Protoss. Some Protoss rejected the Khala out of fear of losing their individuality inside the psychic link and became known as the Dark Templars. They are treated as heretics and forcibly evicted from Aiur. Despite persecutions, most dark templar still seek to defend Aiur in any way they can. Nomadic, they are only known to have settled on the planet Shakuras to study a Xel'Naga temple.

The Protoss are three meters tall humanoids with two luminous eyes, usually gold or blue. With two fingers flanked by two opposable thumbs on each hand, two large toes on each foot, digitigrade legs, broad chests and shoulders with narrow waists, Protoss are very agile and physically strong. A bony crest extends back from the crown of the head, with long neural strands sprouting from its back. These strands facilitate their psychic communal link. Each Protoss has a different skin shade that corresponds to the tribe from which they are descended. The Protoss do not possess any visible ears, mouths or noses, but are able to communicate telepathically and possess strong nasal sensitivities. Protoss do not need to eat or drink, but instead absorb energy from a form of photosynthesis. Their average life expectancy is several hundred years.
Source: StarCraft

ZERGS

Planet of Origin: Zerus
The Zerg were originally small primitive insectoid larvae. Due to Xel'naga manipulation of their evolution, they became able to parasitically merge with other creatures, taking control of their host's nervous systems. From here, they mutated the host and added its DNA to the Zerg gene pool for other Zerg larvae to mutate into. Doing so, they were able to develop into an aggressive space faring swarm sharing the consciousness of a variety of different races assimilated into their genome. Although there is no distinctly typical Zerg, each strains and breeds are based on the original core genus. However some attributes are consistent, such as armored carapace, spines, claws and acid spray.
The Zerg strive for genetic perfection by assimilating other species into their own, creating different strains of Zerg. They did not develop technology, but through the assimilation of other species and directed mutation, thee developed traits to match their technologies. Each strains and colonies possess the traits necessary to fulfill their functions, working as an organ in a larger lifeform. Zerg buildings and units are entirely organic, allowing every Zerg to slowly regenerate if they are damaged. Colonies produce a carpet of bio-matter known as "creep", which provides nourishment for Zerg structures and creatures.
Operating as a hive mind, The Zerg are highly dependent on their command structure: if a Zerg should lose its connection to the hive mind, it may turn passive or go berserk.
The Zerg Swarm is controlled by the Zerg Overmind through its cerebrates. Along with the Overmind, the Cerebrates are the only Zerg with full sapience. Each Cerebrates possess its own overlords for battlefield direction and queens for hive overwatch. If a cerebrate dies, the Overmind loses control of his brood as the vast majority of the Zerg do not have any free will as they are genetically bound to obey the commands.
Source: StarCraft