A niche is a specific, focused topic area or audience segment that a creator or brand concentrates on in order to build authority, relevance, and a loyal audience. On YouTube, niching down — rather than creating broadly — typically leads to stronger viewer retention, higher engagement rate, and more consistent subscriber growth because content aligns tightly with a specific target audience's interests. A well-defined niche also improves YouTube SEO by making it easier for the algorithm to categorize and recommend content to the right viewers. Common YouTube niches include personal finance, gaming, fitness, tech reviews, and cooking.