A traditional macchiato is an espresso with a spoonful of milk foam, tiny and strong. A latte is a tall cup of mostly steamed milk. The big-chain "caramel macchiato" is a different drink again: really a vanilla latte with the shot poured on top and caramel drizzle.
The differences
Milk: a spoonful in a macchiato against 200 ml or more in a latte.
Size: a macchiato is about 40–60 ml; a latte 240–350 ml.
Taste: a macchiato is all espresso; a latte is milky and mild.
The milkiest of the three: lots of steamed milk and about a centimetre of foam, often served in a glass.
How the café in Cuppology builds it
Start with a hot cup.
Pour in the espresso: 30 ml.
Pour in the silky microfoam: 200 ml.
What the café accepts as a latte
Shot: ristretto or espresso or lungo
Coffee 18–90 ml
Milk 170–320 ml
Foam under 16 mm
Milk 40–75 °C
Which should you order?
Pick a macchiato for a strong, quick coffee. Pick a latte for a long, gentle one. If you love the chain version, look at the latte macchiato or caramel macchiato instead.