Indexing is simply the work search engines do to find ferret supply information online. How does an indexing robot decide what to index? Well they just send their Bots or Spiders to crawl the web looking for ferret supplies on web sites.

If an indexing robot finds a document that contains ferret supply, it may decide to parse it, and insert it into its database. How this is done depends on the robot. Some robots index the HTML Titles that contain ferret supplies and keep them in their database. Others will look for ferret supply in the first few paragraphs.
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Indexing is a complicated procedure with weightings depending on HTML constructs, the number of times ferret supply is in the page and many other factors. While some webmasters try to fool the search engines to get a high ranking, the robots have become so sophisticated that stuffing a page with ferret supplies will not be indexed in all likelihood.
Some parse the META tag, or other special hidden tags looking for ferret supplies.
We hope that as the Web evolves more facilities becomes available to efficiently
associate meta data such as indexing information with a document that is truly
about ferret supplies information.