Proto-Indo-European:
* *kwót- - This word meant "what" or "which".
Old English:
* hwæt - This evolved from the Proto-Indo-European root and meant "what" or "which". It was also used as an interjection, similar to "Hey!" or "Listen!".
Modern English:
* what - This form is simply the modern evolution of the Old English word "hwæt".
Interesting Note:
The "wh" sound in "what" is a result of a historical sound shift known as Grimm's Law. This shift changed the pronunciation of certain sounds in Germanic languages, including the "k" sound in the Proto-Indo-European word "*kwót-".
So, while the word "what" might seem simple on the surface, its etymology shows us a complex journey through language evolution and the connections between different languages.