I am new in SEO Field. So please anybody give me some information about H tags - H1,H2,H3,H4,H5,H6 .I only use h1 tag once (central keyword). a h1 is more important than h2 or h6. But a proper use of h2 and h3 tags will definitely improve the search engine visibility. EBAY SEO: THE ULTIMATE GUIDE is a FREE search engine optimization tutorial. Make more money by increasing your rankings in CASSINI - THE EBAY SEARCH ENGINE! What are H1, H2, H3, H4, H5, H6 header tags and how do you use them you Search Engine Optimization. In this video, we cover how, where and when to use These are my notes on using Headings in SEO. In HTML (the markup that makes web pages) the W3C describes Headings, thus: The six heading elements, H1 through H6, denote section headings.