The Presence was created by an american writer Jerry Siegel (co-creator of Superman) and american comic book artist Bernard Bailey. He was created to be the fictional representation of the judeo-christian God, and has also become a notorious character in DC Comics. He is first seen in More Fun in Comics issue #52 that bloomed in the year 1940.
Throughout the history of DC Comics, The Presence has undergone different forms. These forms are the following:
The Voice - When the presence debuted in More Fun in Comics issue #52 he appeared in the form of The Voice which is a discarnate Voice of God.
The Hand - It was first seen in Green Lantern vol. 2, issue #40 whereas an image of a hand appeared out of a random nebula. DC Comics referred to it as a the start of creation of DC Multiverse or also known as the Big Bang.
The Source - In Jack Kirby's Fourth World comics, this form was depicted as a universal spirit. The Source is mainly associated with the New Gods thus believed to be responsible for their creation and empowering them Divine powers.
The Presence - This form takes the Judeo-Christian Deity which is said to be the one who created it all.
As his creator, the Presence mostly features as an idea that Lucifer struggles against throughout the series as he believes that he has no free will as long as he has any connection to the Presence and it's creation, while the Presence argues that Lucifer's own actions are proof of it not being true.
Much of the series also revolves around the Presence vacating its own creation and Lucifer subtly guiding its replacement Elaine Belloc to take its place.
When it's appeared in person, the Presence has appeared as an aging gentleman wearing a bowler hat, dark suit, umbrella and with a grey mustache.
The New 52
While in the past the Presence has mostly remained unseen and unheard of in the main DCU, even to most of the characters connected directly to it, in the New 52 it has manifested a few times to the Phantom Stranger as a Scottish Terrier of different colors, which it has chosen to do because it amuses it. It has also revealed to the Stranger that it isn't supportive of organized religion because it feels these groups have calcified its original intention. The Presence is the creator of the Council of Eternity and stated himself that he was everywhere.
Powers and Abilities
Omnipotence: Being All-Powerful and possesses unlimited almighty power above all in every sense and aspect.
Omnipresence: Being everywhere and nowhere in existence at once.
Omniscience: Know everything and anything.
Being the Supreme being of the entire DC Multiverse and beyond, there is no limit to The Presence's powers and abilities thus proving him to have no weaknesses.