The word 'cookie' is derived from the Dutch word 'koekje,' meaning 'small or little cake.' Apparently, the first historic record of cookies was describing their use as test cakes.
What happened was a small amount of cake batter was baked once in order to test the temperature of the oven. Then rather than waste the batter, it was baked again along with the larger cake, and it would often come out crispy.
The History Of The Chocolate Chip Cookie.
In 1930, a dietitian who owned a tourist lodge was cooking and baking for her guests. Unfortunately, she ran out of the baker’s chocolate she needed for the chocolate cookies that were on the menu. She hurriedly substituted a chocolate bar — cut up into tiny pieces — assuming they would melt. They didn’t — they just softened, instead.
And the chocolate chip cookie was born.
This history of chocolate chip cookies is still alive today, because that woman struck a deal with the manufacturer of the particular chocolate bar she’d used that day: he would print her recipe on his chocolate bar labels, and she would have a lifetime supply of them…
(from Bacon Babble via Presurfer)