Redness, being on and being a baby, are all attributes. Something either has or does not have a particular attribute. Dividing people into male and female is a nominal scale. Putting numbers on buses to identify the route is a nominal scale. Putting numbers on football players to identify their position on the field is a nominal scale.
Arithmetical operations are meaningless on nominal scales.
To add a 44 bus to a 102 bus and get a 146 bus is nonsense. But if data has been classified nominally you can make a Frequency Distribution - you can count how many 102 buses and how many 146 buses there are, for example. The ordinal scale puts things in an order or rank, as well as labelling and classifying them. House numbers are usually on an ordinal scale because 1 is usually at the beginning of the road and the higher the number the further down the road it is. Years are counted on interval scales.