Okay, so milk glass is a type of glassware that's white and looks like it's made out of milk. It's called milk glass because it's actually made by adding something called "opacifiers" to the glass mixture, which makes it opaque and gives it that milky appearance. These opacifiers can be things like bone ash, flour, or even tin oxide.
Milk glass has been around for a really long time, since the 16th century, and was originally made in Venice, Italy. But it became super popular in the 1800s and early 1900s, especially in the United States. People used to love collecting milk glass items like vases, bowls, and plates, and it was even used for things like lamp shades and other decorative items.
One thing to note is that not all white glass is milk glass. Sometimes, clear glass can just be painted or frosted to look white. But true milk glass is made by adding those opacifiers to the glass mixture.
So in summary, milk glass is a special type of white glass that's made by adding opacifiers to the glass mixture, making it opaque and giving it a milky appearance. It's been around for a long time and was really popular for decorative items in the past.