Read our Description, Titles and Keywords article to learn how / why to add this information throughout the pages of your site.
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The name you provide to a page in Weebly is the name given to that page both in the site navigation and in the address of that page on your site. Why is this important? Because if a word is in your address it is seen as more relevant to your site by search engines. More relevant means more likely to to show up in search results.
If you link from one page of your site to another, use descriptive text for the link.
The more sites that link to your own site (as a general rule), the more Google trusts your site to be worthwhile. Think of other people linking back to your site as word-of-mouth that tells not just other people to check-out your site, but tells the search engines to do the same.