You are given a sentence in Spanish. Your job is to translate the Spanish sentence into English.

Cuando oí la extraordinaria charla de Salman Khan, el miércoles, sobre la página de la Academia Khan que le enseña cientos de materias a estudiantes de todo el mundo, tuve una retrospección.
When I heard the amazing talk by Salman Khan on Wednesday, about the Khan Academy website that teaches hundreds of subjects to students all over the world, I had a flashback.