Traditionally, the dining rooms were composed of three essential elements: the table with its chairs, a display case in which to display the glassware and silver (if any) and a farmhouse dresser, also called carving or buffet. The sideboard is a medium height cabinet (the maximum is usually 90 centimeters) with great depth that is usually divided into side doors and drawers in the center.
Like all furniture, the dressers have also evolved and you already find very different designs. Its function is to store the dishes and use the drawers for table linen. Its surface was intended to support plates and dishes waiting to be served. It is very likely that your dining room has to share space with the living room, due to the smaller dimensions of the current houses.
In which case you will surely have to decide between one piece or another (or both if you already have another piece of furniture) but remember that it is a very useful piece to keep and that, in addition, it can be very decorative. On it you can place a still life composed of some important pieces for you and, on the wall, a painting, a mirror or even a vinyl.