True Story: Most of us have believed glass is a solid material as a child (quite rightly), but as we grow up some of us have been told that actually glass is a liquid, which flows very very slowly. They point to the old church window glasses as a proof, as there are old glasses with its bottom thicker than its top.
But the real reason behind this is simply that medieval glaziers couldn't cast perfectly flat sheets of glasses*, and when that happens they preferred to fit the glass with the thicker end at the bottom just as many of us would do.
So the normal state of glass is solid, although it's an "amorphous" solid.
* In fact, we would not be able to produce perfectly flat sheets of glasses until mid-20th century. Sir Alastair Pilkington thought of floating molten glass on a bed of molten metal. As a result, he made it possible to build skyscrapers with glass rather than heavier concrete, which was the standard before then, such as the Empire States Building in New York.
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