A dictionary of search engine marketing terms

IDF = log ( total documents in database / documents containing the term )

Most search engines allow you to see a sample of links pointing to a document by searching using the link: function. For example, using link:www.bm-media.co.uk would show pages linking to the homepage of this site (both internal links and inbound links). Due to canonical URL issues www.site.com and site.com may show different linkage data. Google typically shows a much smaller sample of linkage data than competing engines do, but Google still knows of and counts many of the links that do not show up when you use their link: function.

When search engines search they search via reverse indexes by words and return results based on matching relevancy vectors. Stemming and semantic analysis allow search engines to return near matches. Index may also refer to the root of a folder on a web server.

It is preferential to use descriptive internal linking to make it easy for search engines to understand what your website is about. Use consistent navigational anchor text for each section of your site, emphasizing other pages within that section. Place links to relevant related pages within the content area of your site to help further show the relationship between pages and improve the usability of your website.

Good information architecture considers both how humans and search spiders access a website. Information architecture suggestions:

• focus each page on a specific topic
• use descriptive page titles and meta descriptions which describe the content of the page
• use clean (few or no variables) descriptive file names and folder names
• use headings to help break up text and semantically structure a document
• use breadcrumb navigation to show page relationships
• use descriptive link anchor text
• link to related information from within the content area of your web pages
• improve conversion rates by making it easy for people to take desired actions
• avoid feeding search engines duplicate or near-duplicate content

Internal Navigation (see Navigation)

See also:

• Download IE

Inverted File (see Reverse Index)

IP delivery (see cloaking)

Italics (see emphasis)