Have you ever noticed that when you use Wishes in Genshin Impact that after each pull you get a certain amount of currency that looks like a four-point star?
Those are Stardust and Starglitter. It's a kind of consolation every time you pull from a banner.
Think of them as vouchers you can save up, so you can trade them in for materials that could help strengthen your characters or weapons.
What is Masterless Stardust, and how to get it?
Masterless Stardust is the regular version of the currency, and the most common. You are guaranteed to obtain 15 of them whenever you pull a three-star weapon, which is the most common result during wishes.
You can trade Stardust for common material drops like Damaged Masks, Mist Grass Pollen, Dead Ley Line Leaves, and Adventurer's Experience to name a few.
What is Masterless Starglitter, and how to get it?
Starglitter is the harder-to-obtain version of Masterless Stardust, as they are obtained only when you pull a high-rarity weapon, or a character you already own. The amount awarded varies depending on their rarity, and it further increases if it involves a character with full Constellation.
Because it's harder to get, the trade is much better. You can trade Starglitter for materials like Weathered Arrowheads, Chaos Cores or Ley Line Sprouts. If you save a lot, you can get a high-rarity weapon, either version of Fates that can be used to Wish.
The top prize is one lone copy of a featured 4-star character, and there are two characters featured every month.
You can swap both Stardust and Starglitter in Paimon's Bargains at the Shop, and the store restocks and changes its merchandise at the first day of the month.