Made of oven-safe glass (ideally borosilicate or tempered), so you can bake, serve and sometimes refrigerate/heat in the same dish. For example: “Made from borosilicate glass … microwave, freezer and dishwasher safe.”
Non-reactive material — glass won’t interact with acidic ingredients (e.g., tomato, citrus), so flavour stays true.
Clear/translucent bodies for visibility: you can monitor browning or bubbling through the sides.
Good heat-retention: glass retains heat after removal from oven, helpful for serving hot dishes at table.
Versatile in the kitchen: many are oven-, microwave-, and freezer-safe (depending on manufacturer).
Sizes typically include two different capacities in one set (for example a larger and a smaller pan) to suit various dishes.
Easy to clean, stain- and odour-resistant due to non-porous glass.
Aesthetically pleasing / suitable for serving from oven to table due to glass clarity and design.