I was at a saw shop the other day and someone asked for a chisel bit chain. When I get a chain at the DIY store it comes in a box and the only choices are brand and size. The chain this customer got came off a roll, like a length of rope, the clerk took of a length went in the back and came back out with proper loop of chain for the saw. What is a chisel bit chain? How does the roll of saw chain factor into it?
The comparison of chisel bit chain and regular chain should be Chisel-Bit vs. Scratcher-Bit. Other synonyms might exist.
Near all modern saw chains are a type of chisel bit. The general style would follow some of the examples from the picture below from madsens1.com
Bits pictured can also go by names as semi-chisel (rounded) and full-chisel(square). From left to right the bits above are ranked for ease to maintain and efficiency. The square tooth square grind being the most efficient and arguably the harder of the three to keep sharpened. Number of teeth and gaps in between also play a major roll in an individual chains upkeep and effectiveness.
The first chain saw chains had teeth similar to a common wood saw and are referred to as scratcher teeth. Since they do not have a depth guide like chisel-teeth it made the chain cut slower and inefficient. See picture from Wikipedia
Without going into too much more details some good resources that cover this topic would be