°

Here's a mnemonic means of remembering the difference between the two geographical means of measurement:

Long-itude is the distance ALONG the Equator from Greenwich (in degrees)
and
Lat-itude is the lateral (or sideways) distance North/South from the Equator (in degrees)

Greenwich (London) is at 0° long. and 51½°N. lat.
Accra (in Ghana) is at 0° long. and 5°N. lat.
Quito (in Ecuador) is at 78½° long. and ½°S. lat.

It also helps to recall that one often hears of Northern Latitudes or Southern Latitudes (describing climatic regions) but one never hears of plural Longitudes. The Tropics are good example of specific latitudes.