In addition to the SEO settings in Publishing Pages and Term Sets (for Managed Navigation) In SharePoint 2013 you can also set SEO at Site Collection level. At Site Collection level you can set Meta Tags and XML Sitemap unlike in SharePoint 2010. In SharePoint 2010 though you can add Meta Tags in your Mater Page using the Delegate control or a Webpart of a Custom Control
So In SharePoint 2013 what are the Ot-of-Box Options to SEO a Site Collection.
1. Meta Tags – Now you do not need to add the SEO Tags in your Master Page SharePoint 2013 has a Out-of-Box feature for that. You can add and edit SEO using Search Engine Optimization Settings in Site Collection Administration.
Navigate to Site Settings -> Under Site Collection Administration -> Search engine optimization settings.
Summary : SharePoint 2013 Site Collection SEO,SharePoint 2013 Supports XML Sitemaps
Here you can set Meta Tags for the site.
2. XML Sitemap
SharePoint 2013 provides native support for generating XML Sitemaps. In order to have an XML Sitemap generated for your website you first have to enable the Search Engine Sitemap Site Collection Feature. When XmlSiteMap feature is activated, it registers the site collection with Search Engine Sitemap timer job which runs daily by default.This generates XML Sitemap for every Site Collection that has been registered with that Timer Job. The Search Engine Sitemap job generates not only the XML Sitemap itself but also modifies the robots.txt file where it adds the link for the XML Sitemap file so that it can be easily discovered by search engines.
Another thing to note is that Anonymous access must be enabled for the web application to generate Sitemap else you will be presented by an error message. To view XmlSiteMapSettings navigate to application page(_layouts/15/XmlSiteMapSettings.aspx) where you can specify paths not be crawled by search engines.