Looking for Greek letter clohting but unsure of different kinds of letters. Twill, aplique, sewn-on??? Help!!?

I’m looking to buy a greek letter sweatshirt, and I know that there are a lot of different companies that sell them. However, many different companies have different kinds of letters. Some of them are cloth sewn on letters, while others say twill or aplique. What are the differences between all of these different types of letters. Some of them have a shiny almost silky look to them, and I really love these. What are they???
Please Help!

sewn means exactly what it says, twill is a kind of fabric so that could be sewn or ironed on with a webbing in between that acts as a glue. Applique is also sewn on, sometimes with a thick border of stitches that adds to the design.

For the shiny letters, look for iron ons or any letters made of nylon.

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