Launched in '69, Ariel was for twin-tubs, top-loaders and hand washing. The "bio design" was blue. It would have been P&G's premium detergent, using protease as the enzyme.
Daz would have been the tried and trusted, mid-range, non-bio, twin-tub powder.
Bold was for front-loaders.
When Ariel Automatic was launched in the early '80s, it appeared in a similar box to original Ariel, but the "bio design" was coloured green. The Ariel picture/logo reminds me of an atom, with electrons whizzing around the nucleus.
Due to Ariel Automatic appearing, Bold was repositioned and became 2-in-1, and "Bold 3" for a spell, (cleans, softens & freshens).
In the late 1990s, Ariel had four enzymes, Bold had three, and Daz had two.
Nowadays, Ariel has five enzymes. Persil Bio has four.