Much like rel=”canonical” acts a strong hint for duplicate content, you can now use the HTML link elements rel=”next” and rel=”prev” to indicate the relationship between component URLs in a paginated series. Throughout the web, a paginated series of content may take many shapes—it can be an article divided into several component pages, or a product category with items spread across several pages, or a forum thread divided into a sequence of URLs. Now, if you choose to include rel=”next” and rel=”prev” markup on the component pages within a series, you’re giving Google a strong hint that you’d like us to:
Consolidate indexing properties, such as links, from the component pages/URLs to the series as a whole (i.e., links should not remain dispersed between page-1.html, page-2.html, etc., but be grouped with the sequence). Send users to the most relevant page/URL—typically the first page of the series.