Well, it turns out, it wasn't done for fun. Believe it or not, the QWERTY layout was actually designed to make typing faster and more efficient.
Christopher Sholes devised the current format of the keyboard back in 1870's for their version of the typewriter back then. It wasn't the first keyboard format to come out, but it didn't take much time for it to be widely adopted.
Like moist of us will probably do, Christopher Sholes started with the lexicographic order (A-B-C-D-E), but after hundreds of case studies, he came-up with the QWERTY layout.
Most (if not all) keyboards are on typewriters in the 1870's. Typewriters use metal bars to hold the character alphabets, the other end was linked to carriage with the ink.
When you hit a key, the typewriter would emboss its character on the paper placed under the carriage. However, when an operator learned to type faster, a design flaw comes out.
When you hit two letters in quick succession, the typewriter bars would get jammed and entangled.
After observing how thousands of words were typed, he formulated the format of the QWERTY layout.
Christopher Sholes proposed that letters that are used in pairs frequently (like C-H, S-T, T-H, etc) should be located in different rows. He also thought that the two hands must regularly alternate while typing to achieve faster typing speeds.
He also observed that a vowel is present in almost every word in the dictionary.
According to him, the most frequently used vowel was A and the most frequently used consonant was S. With this logic, he placed A and S together and grouped less commonly used letters like Q, W, Z, X, and C around them.
We've been using his QWERTY layout for over a hundred years now and from the looks of it, we won't stop using it in the foreseeable future.
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