Once upon a time, long long ago, there were no cell phones, and very few people habitually reqched for their pocket every minute.
People spent time looking at the physical world around their bodied, moving around in it, and speaking out loud using audible words. When somebody wanted to write a document, rather than confusedly tapping a screen with their thumbs, or speaking it to a datacenter and marketing algorithm that transcribed it, people would use something called a "keyboard" to write the document. Keyboards were large arrays of switches that would not fit in your pocket or even a briefcase generally.
