"Most" means nearly all. The "majority" means over 50%. In everyday usage, "most" is the more frequent expression. When ESL learners say "the majority of", most of the time it's a translation from their native Romance language.

I save the word 'majority' for things where at least some kind of counting has gone on. I think! So I'll talk about the majority of voters, or the majority of the applicants, or the majority of the burgers served by a particular restaurant (if I've got some kind of fact to support that - perhaps a newspaper article). But if I'm not counting I'll just say, most of the tourists in France, most people, most of the people in Iceland, etc. I'm not counting. I mean, like, 80% or more. Maybe! I'd rarely say the majority of the milk has been drunk. I'd just say 'most'. But I suppose if I had been counting/measuring the amount consumed then maybe I would! (????) I think maybe the difference between MOST and MAJORITY is an ART not a science?

The meaning is similar, although ‘most’ tends to suggest a larger proportion than ‘the majority’. ‘Most’ is informal and normally used in conversation ; ‘the majority’ is formal and more likely to be used when writing a report or making an official statement.

When we are talking about the majority of something in general, we use most + noun. When we are talking about the majority of a specific set of something, we use most of the + noun