Quirk moulding is a type of decorative trim used in woodworking projects, typically around doors, windows, and baseboards. Other synonyms for quirk moulding include "bead and quirk," "cove and bead," "double bead," and "step bead." Each of these terms describes a different style of moulding with subtle differences in shape and profile. Bead and quirk moulding features a small, rounded bead along with the distinctive quirk, while cove and bead has a concave curve and bead shapes. Double bead is similar to bead and quirk, but with two lines of beads instead of one, while step bead has a series of small steps along with the bead and quirk.