Degree sign

It means degrees: of heat, of angle or on a map. In 25 °C or 77 °F the letter names the temperature scale: Celsius in most of the world, Fahrenheit mainly in the United States. On its own, as in 90° or 360°, it measures an angle or a turn. In coordinates such as 48°51′N it gives latitude or longitude, followed by minutes (′) and seconds (″).

Many forecasts and weather apps show just 30°, relying on the local scale or your settings. In a message to someone in another country, add the C or F.

Does ° touch the number or take a space?

Angles touch; formal style spaces temperatures before °C. Write 90° and 41°N with no gap. International System of Units (SI) style writes 25 °C: a space before the sign, none between ° and C. The closed form 25°C is common in everyday text; follow your publication's style, but never split ° from its C or F.