The execution scene is the most painted moment in the Gospels involving a woman, and most of what people picture is not in the text.
Mark gives it fullest: Herodias' daughter dances at Herod's birthday feast, pleases him, is offered up to half his kingdom, consults her mother, and asks for the head of John on a platter. Matthew shortens it. Luke omits the scene entirely, and John does not mention the death at all.
The girl is not named in any Gospel. The name Salome comes from Josephus, who gives Herodias a daughter of that name in his genealogy of the Herodian house without connecting her to John's death. Joining the two is an inference; it is a good one, but the identification is made by us, not by the sources.
The dance is described in one word. There is no description of it, no suggestion of seduction, and nothing about clothing. The Dance of the Seven Veils was invented by Oscar Wilde for his play Salome in 1891, given music by Richard Strauss in his 1905 opera, and passed from there into film, painting and general knowledge. It is a nineteenth-century French and English orientalist fantasy, and it is now so firmly attached to the story that people encountering the Gospel text for the first time often assume something has been left out.
Late antique and medieval retellings had already begun the drift, and by the Renaissance Salome was being painted as a temptress rather than a girl following her mother's instruction. The text has no interest in her motives at all: it gives them to Herodias.