Perhaps this will help clear things up.
The classification by bevel is correct as previously stated. The low angle jack plane was introduced by Stanley in 1905 as a #5 Jack plane modified with block plane characteristics. Modern planemakers have extended the idea to other bench plane sizes, calling them "low angle jointers, low angle smoothers", etc. The difference is that with bevel up block planes, the angle you sharpen the blade at determines the cutting angle, whereas with bench planes, the cutting angle is decided entirely by the frog angle, independent of bevel angle. The functional distinction allows a lower angle of attack of the blade to the wood, permitting better cutting through grain fibers, particularly end grain. Also, because the bevel is up, you cannot support the blade near the cutting edge with a chipbreaker, as the bevel itself is the chipbreaker, so to retain a stiff edge, the blades tend to be thicker than with bench planes.
See
http://supertool.com/StanleyBG/stan9.htm#62 Low Angle Block plane, 14"L, 2"W, 3 5/8lbs, 1905-1942. *
This is one of Stanley's better planes they ever decided to manufacture. It is nothing but a jack plane with the block plane mechanisms added to it, instead of the common bench plane mechanisms. It has its cutter seated at 12 degrees, an adjustable mouth, and the depth adjustment knob like that found on the other block planes in this series. There are several things to check out on this plane, before purchasing one. Since the cutter is seated so low, and the fact that this is a powerful plane (pushed like an ordinary bench plane), the mouth often chips, especially in the area behind the cutter. You can flip over ten of these plane, and eight of them will be chipped, one will not be chipped but repaired, and the last perfect. You also want to check the side walls of the plane, down where they blend into the heel and toe - these two areas are prone to chipping.
The front knob is turned from rosewood and is unique to this plane. The knob sits atop a nickeled cast iron disk that has two projecting nibs on its top to fit into the underside (endgrain) of the knob. The disk is threaded to the bolt that passes through the knob and into the sole. The bolt needs to be tightened securely to the disk, placing pressure on the knob, so that the knob doesn't spin as you twist it to adjust the sliding section. Many times the bottom of the knob is split out or has a circular groove cut into its bottom since it's not secured tightly to the disk. If the knob is split badly, you may have to turn another one in order to adjust the plane as intended. The bolt threads into a boss in the sliding section. Sometimes this boss chips out, and won't grip the bolt well, making the plane less valuable for use and/or collecting. You should back the knob out completely to examine the boss. The boss can also strip (or the bolt itself can do the same). Be sure that the knob seats firmly and turns freely when it's screwed tightly.
The plane has the common eccentric lever to adjust the long sliding section of the sole. This adjuster is unique to the plane. The rosewood tote is also unique to the plane as its toe is shorter than that used on the smaller bench planes, like the #3, since the adjuster needs some room to work through its range. The lever cap, activated by a knurled thumbscrew, is nickel plated and has a keyhole-shaped cutout through which the lever cap screw fits. The nickel plated adjuster has a knob that's larger in diameter than the similar ones used on the smaller low angle block planes, like the #65; you can tell if this adjuster is proper to the plane by looking at how far off the main casting it sits - it should be no more than 1/8" above the casting. The bolt head used to secure the rosewood tote to the main casting is nickel plated. The contrast between the japanned interior, the nickel plating, and the rosewood give the plane a stunning look when new.
Today, a lot of handplane lovers are buying a modern copy of this plane to use as a smoothing plane. So there we have it, smoothing planes have now been stretched to 14" long, probably because longer is better they think. I'd sure hate to use a plane this long to smooth a stubborn 1" area of tearout. Must be because I don't get it, or something. Stanley mustn't have gotten it, either, as they advertised as being designed for heavy work across the grain. Doesn't sound like smoothing to me.
One of Stanley's competitor's, Sargent&Co., made a version of this plane.