If you want a pocket knife for regular use, search for a folder that easily fits your pocket or belt when in a closed position. The knife should be light enough to carry comfortably; the blade and handle need to suit your hand.  Folding knives are a safer choice as they don’t close the knife abruptly while in use. In addition, the locking blade is stiff enough to be manipulated according to the task at hand. Also, consider the metal spine of the blade. The most common are stainless, carbon, and tool steel.