Short answers, pulled from the story.
Mary Shelley's 1818 novel does not give the creature a specific name. Victor Frankenstein calls him the "creature", "fiend", "wretch", and several other terms; the creature refers to himself as a "monster" at least once. The name "Frankenstein" was applied to the creature by popular usage within a decade of the novel's publication, not by Shelley.
Shelley describes the creature as 8 feet tall with lustrous black flowing hair, pearly white teeth, and limbs selected for beauty. His yellow skin barely covers the muscles and arteries beneath, and his eyes are watery, nearly matching the dun-white color of the sockets around them. He is far more flexible in his movements than the stiff-legged figure shown in most films.
Makeup artist Jack P. Pierce designed the look for Boris Karloff's portrayal in the 1931 Universal film Frankenstein. Pierce based the creature's distinctive flat-topped head on a drawing made by his daughter, which she had produced from a dream. Universal secured the copyright on that makeup format, and subsequent actors in the franchise replicated Karloff's look.
The image of Boris Karloff's face as the creature is owned by Karloff Enterprises, a company belonging to Karloff's daughter. She secured ownership through a lawsuit in which she was represented by Bela G. Lugosi, the son of actor Bela Lugosi. After the lawsuit, Universal replaced Karloff's features with those of Glenn Strange in most of their marketing materials.
In Shelley's novel the creature is sensitive, articulate, and deeply emotional. He is a vegetarian, learns to read and speak French and German within 11 months, and is fluent in English by the novel's end. He reads Paradise Lost, Plutarch's Lives, and The Sorrows of Young Werther. His primary desire is love and acceptance; revenge follows only after he is rejected by everyone he encounters.
Scholars have read the creature as an analogy for a motherless child, a symbol of an oppressed class, and a warning about uncontrolled scientific progress. Some have connected him to Benjamin Franklin as a representation of the new American nation. Researchers including Anne Mellor, John Malchow, and Karen Lynnea Piper have separately argued that the creature's physical description carries racial coding drawn from 18th and 19th century discourse on race.