Iced coffee is hot brewed coffee, poured over ice, served cold. It is bright, acidic, and it tastes like the beans it was made from. Cold brew is coffee brewed with cold water over 12+ hours, without heat ever touching it. It is smoother, less acidic, and it tastes muted — the notes that heat draws out of the bean stay dormant in cold water. These are two very different drinks.
Almost every American coffee shop calls both drinks “iced coffee” on the menu. This is a marketing decision that is understandable and a cop-out. If you are drinking “iced coffee” and it tastes flat, smooth, less like coffee than you expected, you are drinking cold brew. If it tastes bright and acidic and a little sharp, you are drinking real iced coffee.
Which one you prefer says a lot about you. People who want their coffee to taste like coffee prefer real iced. People who want a cold caffeine drink that is easy to swallow prefer cold brew. Neither is wrong, but the two have gotten confused in a way that lets bad cold brew hide behind good coffee’s reputation. Ask which one your cafe is actually serving. About 40% of the time the barista will be surprised you asked. About 20% they will smile like you finally got it.