Niehaus, the Chief Engineer in the Power Tool Division for Rockwell International, in 1964. The miter saw showcased several innovations still found today: radial arc spring action, blade braking and dust collection. Rockwell did not patent the design, leading to a large number of manufacturers and innovation improvements. The power miter saw makes cuts by pulling a spinning circular saw blade down onto a workpiece in a short, controlled motion. The workpiece is typically held against a fence, which provides a precise cutting angle between the plane of the blade and the plane of the longest workpiece edge. In standard position, this angle is fixed at 90°. A primary distinguishing feature of the miter saw is the miter index that allows the angle of the blade to be changed relative to the fence. While most miter saws enable precise one-degree incremental changes to the miter index, many also provide "stops" that allow the miter index to be quickly set to common angles (such as 15°, 22.5°, 30°, and 45°). Types There are several types of miter saws: Original miter box and saw - The first miter saws usually consisted of a wooden or plastic three-sided box with 90° and 45° slits to guide a hand or back saw to make miter cuts in a piece of work. Power/Standard miter saw - A powered version designed generally for making straight cross cuts on a piece of work at a wide range of angles (unlike an abrasive saw which can only cut 90 degrees to the board). They are commonly used to create 45° degree straight cuts for framing. Compound-miter saw - Compound miter saws have the added benefit of being able to tilt the blade and head at a variety of angles to the workpiece. This makes bevel cuts possible. A bevel cut is a ramp angled cut into the side of the wood. This type is commonly used in trim work for homes. A compound cut is a combination of a miter and bevel cut. Dual compound-miter saw - Dual or double compound saws allow the head to rotate when angled on both the left and right hand sides. This means all angles are achievable without repositioning the workpiece. Sliding compound-miter saw - Sliding miter saws are able to move the saw head back and forth on a sliding rail, similar to a radial arm saw. This increases the size