′ ″
The signs for minutes, seconds, feet and inches — forever impersonated by the apostrophe.
The prime ′ marks arc minutes and feet; the double prime ″, seconds and inches: 23°33′S, 5′11″. They are slanted on purpose, drawn to keep company with numbers.
The straight apostrophe and the straight quote are the usual impostors — and the curly ones look even worse in the primes' role. The entities are ′ and ″.
Wrong: 23°33'S, 5'11" tall (apostrophe and quote faking it)
Right: 23°33′S, 5′11″ tall (prime and double prime)