What is “single-bevel” blade?

It is a type of blade that has sharpened only on one side. Most of the Japanese fish knife (IST-05 DEBA knife) and sashimi knife (IST-06 Yanagi knife) are single-bevel, while general utility knife such as cook’s knife (G-2 Cook’s) and santoku knife (G-46 SANTOKU) are double-bevel.