Whenever I see text written in ALL CAPS I ask the person who has written it if they know why it’s not a good idea to type everything in CAPS and most don’t know the reason. I’ve had to explain it so often that I thought a quick explanation for all to see may be of value.
Our brains interpret words that we read by “Shape” before actually reading the word. So if we recognise the shape, in the context that it appears it’s very fast to read. Conversely if what we are reading is in CAPS then our brain has to slow-down and focus on each letter of each word and “manually” read it.
As you can see the first example has “Rectangles”, only as their shape; yet the second example has very distinct shapes.
Proof that this works is that when you are driving and you approach a road-sign with a Street Name, Suburb Name etc. you are able to recognise the word long before it is clear-enough for you to actually read the words and letters that make-up the word.