If you really want to snowboard but don't know what gear to buy, we're here to help.
You should get a board that fits not only according to your height and weight, but your performance level. Boards may all look similar, but each one has a different flex and intended use. Beginner riders should size their board length to the height of their chin and it should have a softer flex. This makes the board more forgiving and easier to turn.
More advanced riders are better off with a board that comes up to the height of their nose or eyes and has a stiffer flex to handle higher speeds. The exception to this is someone that wants a park board. In that case, you will want a board that is softer and shorter than normal.
Sidecut refers to the width of the board at the tip, waist (middle), and tail. Most boards will have very similar tip and tail dimensions. When the tip and tail widths are the same, this is usually a board that will excel in the park. A board with a tail much narrower ("20mm) than the tip is designed for carving. The wider the waist, the better the board is for powder or for someone with a bigger boot size.
Contact length is how much of the length of the board makes contact with the snows surface on a normal groomed slope. This differs from the board length because the tip and tail are turned up and don't make contact with the snows surface.
Effective edge is the amount of board that touches the snow when the board is tipped on its side, for example, when you are making a turn. The higher the ratio between effective edge and total length, the more a board is designed for groomed runs. More edge equals better grip on hard pack but also makes for a tougher landing when doing tricks. Effective edge and contact length are usually similar, but may not be identical because of camber or other board shape features.
Nose/tail length is the length of the part of the tip and tail that does not touch the snow if the board is laying flat. Longer tail lengths and boards with similar nose and tail lengths will signify a park board because you have more area to land and can land facing either direction.
Sidecut radius determines how short of an arc a board will naturally make when on its edge. A smaller number means a board will have a short natural carve arc. Shorter boards will always have a smaller radius than longer boards, so comparing different sizes is fairly meaningless. Powder and park boards will generally have a longer turning radius because you do not want the board to turn on its own.
Camber refers to the arc in the board itself when laid flat on the snow. Park riders generally want more camber because the board will 'pop' easier for tricks.
Rocker is where the nose and tail rise off of the snow a bit earlier than usual, making for superb float in powder and easier turn initiation on groomed runs.
Stance width is the allowable distance between feet that the various binding mounting holes on the board will accommodate.
Stance offset is how far forward the center point of the binding holes are. Park riders want a smaller number than all mountain riders because they want a more even distribution of weight for riding switch (when the rear of the board is pointing forward.) Unless you have a very wide stance, the offset probably won't matter what terrain you wish to ride. You can use a variety of the boards hole patterns to choose where to mount the bindings.