Languages have different structures. Some languages, like German or Spanish, have grammatical genders. Some languages, like Greek or Russian, have an additional color for blue unlike English. Do these differences mean that speakers of different languages perceive the world differently? The original theory, known as linguistic determinism, is the idea that language determines thought (and not the reverse). The weaker version of this theory, linguistic relativity, is that language might influence thinking.
Here are three videos that 1) introduce the topic 2) give evidence of how language affects thoughts 3) give some concrete examples of how this theory can be harmful.