Branded keywords are words or phrases, including brand names, and are used by people in search engines to find pages and information in niches.
Keywords, in SEO, represent the words (or phrases) used by people to look for information across search engines (e.g., smartphone reviews). Branded keywords are search words or phrases that include a brand name (e.g., iPhone reviews).
People tend to search for everything on the web, and branded keywords are used by searchers to find niche information about a specific brand that they've heard of already. A strong strategy regarding the right keywords to use and how to create new content to target those specific keywords will help any website owner.