Redirection vs Pipes

What is the difference between the statement cat volcanoes.txt | wc and the statement wc < cat volcanoes.txt. In both cases, isn’t the output of cat volcanoes.txt being redirected into wc?

Link to my exercise: Pipes.

Le pipe te sert a scinder deux commandes différentes, ici tu concatenes volcanoes.txt et tu, avec le | , demandes a ton ordi de compter les mots dans volcanoes.txt : cat volcanoes.txt | wc