When we hear of a "slipper", we often think of the cozy and comfy type of footwear that is worn indoors to keep our feet warm.

The pair of ruby slippers that Judy Garland wore when she played Dorothy in The Wizard of Oz are shoes or mid heel shoes, but they can also be called slippers because they don't have any typical laces and therefore you don't have to tie them. In other words, you can just "slip" your feet in them.

In everyday conversations, most people would normally just call them "shoes", but calling them "slippers" is a correct term too. Just some interesting information to solve your curiosity about Judy Garland's ruby slippers, or "ruby shoes" if you like to call it that way.   
 































Article: Ruby slippers worn by Judy Garland as Dorothy