Why did old typewriters not have a number one key?

When looking at old typewriters, you’ll notice the key for number one is missing.

It’s not because someone took it out or because it broke. Here is another one:

So did you find out why the one key is missing?

Here is the answer: the number one key was not implemented by design. Instead, the L key – l – in lowercase, was used in its lowercase form as a letter or a number, because a  lowercase l looks like a one. That allowed manufacturers to save some space in the overcrowded area where hammers were located.