I wouldn't use that website as any sort of guide. A lot of misinformation (eg. Bread knives are 5" long, cleavers are ment to hack bones and somehow stay sharp because of their shape???, etc.)
Quotes from the site:
" A lot of cooks and professional chefs prefer to buy knife sets because they can get a variety of knives for one price."
"The best knives are made out of a single piece of hand forged steel"
"The best knife blades are ceramic because it can be sharpened to be made as sharp as a scalpel, stay sharp for a long time, and they do not rust."
:scratchhead: