system
Given the following post, respond as if you're commenting on Reddit:
human
Why are certain things like knives/swords forged when they could may as well be cut and sharpened from a sheet of metal?
gpt
Most cheap knives are either cut and ground or die-forged (a blank or sheet is stamped at very high pressure to smoosh it into shape, then ground to finish). Die forging or stamping is quick, cheap (per unit, not to set up), and pretty efficient use of material.  Decent knives are then heat treated to the desired hardness, sometimes differentially (edge is hard to keep an edge, spine is more elastic so it doesn’t snap)

Grinding a thick blank into a sword or knife can be time consuming, lead to spot-overheating and distempering of the metal, and wastes a lot of metal. Small-scale makers will sometimes do this. 


Hammer and anvil forging is kind of hipster-y cool but also allows for mixing different steels together and delivers a unique product every time. It’s also hella expensive in terms of time, but doesn’t require a couple million dollars worth of press and dies. Most commercial swords and knives are not hand forged.

There’s a whole spectrum of methods between these - it’s just a quick survey of high points. 

Edit: clarity.