Abstract: A lamp includes a lamp body; and an illumination assembly including a lamp shade assembly including a shade and a seat; and a lamp board. The seat is threadedly secured to the lamp body. The lamp board is secured to a lower end of the seat and laterally extends out of the seat. The lamp board serves as a bottom of the seat. The lamp board includes two first electrodes fastened on a bottom and a plurality of second electrodes adjacent to an edge. The first and second electrodes are electrically connected to positive and negative terminals of a control circuit of the lamp board respectively. The first and second electrodes are positive and negative terminals of a light source respectively. A clockwise rotation of the illumination assembly threadedly secures to the lamp body and turns on the light source.