Emotional Embodiments
The energies created by the emotions of sentient life are personified as sentient beings comprised of those energies.
Overview
At the beginning of the universe, the Emotional Spectrum was created with the first sentient life form. With the first sensations of sentience came thoughts and emotions which never existed before. With more and more use, each emotion gained footing throughout the universe. These emotions gathered energy which coalesced into the Emotional Spectrum. And with the gathering of each band of emotional light came sentience to each emotion.
There are apparently seven emotional entities - each one corresponding to one of the seven bands of light in the Emotional Spectrum. These embodiments of emotion have existed ever since, but are only now being discovered by the Guardians of the Universe, those who serve them known as the Green Lantern Corps, as well as others who have entered into the War of Light.
The Entities
Only a handful of the Embodiments have revealed themselves personally. In Green Lantern v.5 #52, The Entity showed their creation to Sinestro. Though, they may all come to be known by the universe soon enough.
The Butcher - Rage Entity

With the first act of Rage, the murder of Abel by his brother Cain, the Rage Entity came into being. The Rage Entity is the avatar of the Red Lantern Corps, though none of its members have come across it. It resembles a bull, with horns that mimic the shape of the symbol of the Red Lanterns. The Rage Entity once came into conflict with the Spectre who has warned Atrocitus not to go searching for it. It's name was revealed in Green Lantern #54. He was captured by Atrocitus and put into his battery until Krona broke it to release him. Now he is under the control of Krona and has been take to the Lost Sector of the Universe.
Ophidian - The Tempter

The Avatar of Avarice came into being after a serpent in the Garden of Eden consumed that which he did not need. The entity of greed was captured by Larfleeze, and stored in the only existing Orange Power Battery. It has spoken to Hal Jordan when the power battery was in Jordan's possession. It's name was revealed in Green Lantern #54 as the Ophidian. Ophidian later escaped and possessed Hector Hammond and they then went to find Carol Ferris. He reappeared to stop Jordan, Atrocitus, Indigo, and St. Walker using Hector's psychic powers. He disappeared along with Krona and the other entities to the Lost Sector. On his head is the symbol of avarice, and the Orange Lantern Corps.
Parallax - Entity of Fear

Parallax is the living embodiment of Fear, a demonic parasitic entity which would travel from world to world, causing entire societies to destroy themselves out of fear and paranoia. The yellow fire of fear has been tapped into by Sinestro who then founded the Sinestro Corps, and Parallax feeds off the terror its members produce. It was revealed to have been created by the fear insects felt when they were chased down by creatures which evolved from the sea-based lifeforms. The first insect to feel fear became Parallax. Parallax was kidnapped by Krona, who seeks to capture all the entities to find the source of life, and taken to the Lost Sector.
Ion - Embodiment of Willpower

Born at the beginning of the universe, with the first act of willpower, Ion is a cosmic entity. Ion is the living embodiment of the willpower in the universe and came into being when the first sentient creature willed itself to move. It is a passive creature, living in symbiosis with it's host as opposed to the parasitic relationship some of the other Emotional Embodiments employ. The green might of willpower was discovered by the Guardians who utilized it to create their intergalactic police force, the Green Lantern Corps. The Guardians have used Ion as a weapon of sorts, selecting a GL, such as Sodam Yat, or Kyle Rayner to host it to use it's power for the Guardians purposes Ion was kidnapped by Krona, who took parallax and the other entities to the Lost Sector. Hanging from it's chin is a growth that resembles a smaller, more rounded Green Power Battery.
Adara - Hope Entity

The Entity of Hope is a being created from the first act of prayer from a sentient being caught in a fierce storm.
The blue rays of hope are utilized by the Blue Lantern Corps. It's name was revealed in Green Lantern #54 as the Adara. It has been captured by Krona and taken to the Lost Sector. It is a bird with two heads sprouting from the sides of a third, and the symbol of hope on it's torso spreading out across it's wings and neck. It bonds with Nicole Morrison, a girl who was kidnapped and attempts to escape.
Proselyte - Entity of Compassion

As Rage was born of murder and Hope was born of prayer, Compassion came into being to alleviate suffering. As it reached out to offer itself to all living beings, Compassion took on a form similar to a octopus.
It's name was revealed in Green Lantern #54 as the Proselyte. It has been captured by Krona and taken to the Lost Sector.
Predator - Body of Love

The Predator is the sentient embodiment of Love. Little is known of this entity except, like it's 'siblings', it can possess a physical body. Unlike the other entities, it is the only one, so far, which has shown to be able to create a corporeal, crystalized form of it's own. It also appears to be the only entity that can be corrupted by the host it inhabits. The violet aura of love was harnessed by the Zamarons, incorporating their Star Sapphire gems into the creation of the Star Sapphire Corps. Is being protected by the Zamarons and Carol Ferris. It possesses a man named Abraham Pointe, who has been taking pictures of a waitress he finds attractive, in an attempt to show him what love truly is.
Black Hand

Black Hand is the herald of Nekron, Lord of the Unliving. Originally a minor Green Lantern adversary, he had recently discovered the power of death, and has spent several years preparing for the advent of Blackest Night.
After a final visit to his family, he used his cosmic divining rod to kill himself. Immediately he was resurrected, finding himself in the company of the scarred Guardian, who pronounced him to be the embodiment of the black light, a being equal to Parallax, Ion and Predator.
He was the first Black Lantern. At the end of Blackest Night he was blasted with white light and making him live again. Then he was shown with the indigo tribe held captive with the same chains holding Nekron. He was brainwashed by the Indigo Ring into feeling compassion. However, he has recently been freed of this state due to the shattering of the Indigo Power Battery. After committing what appeared to be suicide when the Battery was fixed and the Ring he removed came after him again, Black Hand was brought back by a black power ring that he regurgitated.
The Entity

The Entity is responsible for life in the DC universe. It was uncovered by Nekron during the Blackest Night.It temporarily made the White Lantern Corps and made hosts of Sinestro and Hal Jordan. It is now in the form of a White Power Battery.
It brought back twelve people to protect Earth during the Brightest Day and gave them each a mission to complete in order to find the new champion of life.
New Guardians

The entities were being hunted by a mysterious enemy of all the corps. All of the Lantern Corps representatives from the Blackest Night were being gathered once again to face an ancient enemy of the universe. They sought to gather each of there corps entities then go there separate ways. but they were beaten by the enemy who has turned out to be Krona. Krona has now collected all of the emotional embodiments and now is using them to exact his revenge on the Green Lantern Corps. To do this, he placed Parallax into the Green Lantern Central Power Battery on Oa to restore the yellow impurity to the rings, and used the impurity to control the Green Lantern Corps, while having Mogo jettison rings so that more Green Lanterns would be recruited and immediately brainwashed.. He then had the other entities possess the remaining Guardians on Oa.
Emotional Spectrum
The energies created by the emotions of sentient life, visible as different wavelengths of light.
The Emotional Spectrum was created early on when sentient life first appeared in the universe and its thoughts and feelings became powerful enough to coalesce into in a whole band of energy. This band of energy conformed to the spectrum of visible light with red, orange, yellow, green, blue, indigo and violet all corresponding to a specific emotion. Each band of emotional energy is represented by a corresponding Emotional Embodiment.
Rainbow Girl, a substitute Legionnaire in the 31st century, is known to be able to access the full powers of the Emotional Spectrum.
The Spectrum
Red Throes of Rage

As an energy on one of the far ends of the Emotional Spectrum, the Red Light of Rage has an overpowering effect on the thoughts of those who managed to wield it, and its energy often coalesces as intense heat that burns as long as the anger is there to serve as its fuel. The overwhelming power of the Red Light can often burn away the power of most other lights in the spectrum. Atrocitus of the Five Inversions managed to harness the red light in a Central Battery on Ysmault to power his Red Lantern Corps. The Red Lanterns become so consumed with rage that they are literally filled with its red energy, which replaces their blood and heart.
The Emotional Embodiment of Rage is The Butcher.
Orange Light of Avarice

As the pure light of greed, exposure to the orange light can have addictive effects on sentient beings who try to wield it. Its consumptive power can also drain the energy from most other lights.
The Orange Light was harnessed into a power battery thousands of years ago by a number of beings, who made a deal with the Guardians of the Universe to keep it. In the thousands of years since, it has stayed buried in the planet Okaara of the Vega System. Larfleeze is the last surviving keeper of the Orange Light and uses it to create his Orange Lanterns.
The Emotional Embodiment of Avarice is Ophidian.
Yellow Fire of Fear

First harnessed by the Qwardians,who slowly killed off a planet they held dominion over in order to access it, Sinestro would later wield the Yellow Light and use it to establish and empower his Sinestro Corps as a dark mirror of the Green Lantern Corps. The Yellow Light has the specific ability to weaken the strength of the Green Light of Will, making it the perfect weapon against Green Lanterns who have not confronted their fears.
The power of the Yellow Light grew intense enough to summon forth a monstrous elemental that completely embodies fear. This being became known as Parallax.
Green Might of Will

As the balanced and center color of the Emotional Spectrum, it was the power of the Green Light that the Guardians of the Universe chose to harness for the foundation of the universal police force, the Green Lantern Corps. Despite the fact that 'will' is not technically an emotion, it is still included as one of the better-known Lantern groups.
The Emotional Embodiment of Will is Ion and inhabits the body of Sodam Yat.
Blue Rays of Hope

Said to be the most powerful light of the Emotional Spectrum, the Blue Light apparently has the drawback of being dependent on the Green Light of Will to be utilized to its full power. This symbiotic relationship also strengthens the power of the Green Light when its wielded in the vicinity of a bearer of the Blue Light. The Blue Light was channeled by two exiled Guardians, Ganthet and Sayd, to create the Blue Lantern Corps.
The Emotional Embodiment of Hope is Adara.
Indigo Glow of Compassion

Discovered by the Green Lantern [[Abin Sur]], the Indigo Light is shown to shine compassion on to those who wear an indigo ring. It is wielded by the group calling itself the Indigo Tribe, formerly made of the worst sadists and psychopaths in the galaxy, now seeking to spread goodwill throughout the universe. A female calling herself Indigo appears to be the leader of the Tribe. Their indigo rings allow them to replicate the power of the other six corps; an agonizing Green Lantern was given a mercy killing when exposed to the staff, while a Sinestro Corpsman was in turn overwhelmed by a massive yellow construct and scared away.
The Emotional Embodiment of Compassion is Proselyte.
Violet Aura of Love

Like the Red Light, the placement of the Violet Light at the far end of the Emotional Spectrum means it can have a particularly overwhelming influence on the minds of those who wield it. The power of the Violet Light was discovered by the Zamarons, who found the remains of two embracing lovers fossilized in violet crystal. Their first attempt to harness this power proved its overwhelming effects, as the original Star Sapphires possessed a rabid obsession in their pursuit of love. The Zamarons have since refined their methods for channeling the Violet Light with their new Star Sapphire Corps through new Star Sapphire Rings and Batteries fueled from a massive super battery on Zamaron.
The Emotional Embodiment of Love is The Predator.
Ancient Predecessors
The Glow

Billions of years ago, long before Earth was around and when Sol was a new star in the universe, the people of Oa (who would later call themselves Guardians of the Universe) were just beginning to scratch the surface of their newfound power. This power was utilized by Killala, the then-love of Dream of the Endless, and her people. This power was personified in Sto-Oa, the sun of Oa, and the being who stole Killala from Dream.
The Oans experimented with this power. The Glow manifested itself as a green fire when utilized by the Oans, specifically Killala. It would take eons for the use of the Glow to become refined in order for it to be wielded by the Green Lantern Corps.
Energy Constructs
Energy constructs are used by most members of the Lantern Corps. The Constructs are generated (usually) by power rings that members of the Corps use. These constructs vary in form based on the wielder's imagination. Depending on the Corps or the wielder, there may be limits or different styles to the constructs.
Red Lantern Corps

It is not typical for members of the Red Lantern Corps to create constructs with their crimson energy, as rage is one of the most difficult areas of the spectrum to control. Red Lanterns typically are only able to spew their energy in berserker fashion from their mouths or rings. The exception to this has been when a red ring takes control of a green lantern, such as Hal Jordan and Guy Gardner, who used the red energy to create weapons and unleash their anger. Also, the energy of a Red Lantern is different from other Lanterns as it appears in more of a liquid form like fiery blood.
Orange Lantern Corps

Members of the Orange Lantern Corps are not actually living as all members were killed by Larfleeze, the only living member, and are actually "avatars" of the fallen made from the constructs of the Orange Power Battery.
Sinestro Corps

The energy constructs of the Sinestro Corps are quite similar to the Green Lanterns in the sense that they can create anything imaginable. The only difference is that their rings are powered by how much fear they can strike into their enemies. For this reason many Sinestro Corpsmen will create constructs that are terrifying and even play on their opponent's specific fears.
Green Lantern Corps

The green power ring, the first known weapon to harness the power of the emotional spectrum, creates solid-light constructs based on anything the wearer can imagine. They can be weapons, tools, anything at all as long as the wielder has sufficient willpower and imagination. The detail and style of these constructs vary greatly among lanterns as well as the type. For example, John Stewart being an engineer creates each of his constructs with perfect detail, every last bolt being in place while Soranik Natu as a doctor creates many weapons that resemble medical instruments.
Blue Lantern Corps

The Constructs of the Blue Power Rings are based on the psyche of the target, taking the form of whatever gives hope to the target. The first example of this took place during the "Rage of the Red Lanterns" story arc when Saint Walker's ring created a light construct of Katma Tui for John Stewart.
Indigo Tribe

Members of the Indigo Tribe are unique in that they possess both a power ring and a staff that can channel emotional energy. Their staff has the ability to manipulate the energy of the other emotions of the spectrum. They are able to create any color light construct for this reason as long as they have that color lantern in their vicinity.
Star Sapphire Corps

The Star Sapphires of Zamaron can also create constructs to aid them in battle, however theirs have a slight difference from the constructs of other rings. Sometimes the violet light will come from their rings as pure light but sometimes their constructs will take a crystalline form.