Both - but very comfortable. I have flattish feet and distorted toes and thought I should try a pair to see if they made any difference - "Why bother now?" said the physio - and they certainly do. I'm still at the adjustment stage ie only running on grass in them and only for three or four miles. Only grouse is that they are a silly price and the nearest supplier is 40 miles away, so I have had to begin with a 'pre-loved' pair from Ebay.I can't decide whether those [Vibram Five Fingers] are creepy or hilarious.
Round the house and up to the shops - Crocs. But not the absurd £30-45 officials, when every shop sells versions which are functionally identical. Mine are £4.99 Lidl jobbies and have given three years of constant use. I don't know what polymer they use but it is dry and grippy in all conditions and I'm generally a Sweaty Betty in sandals: I can't wear flipflops even if I wanted to.