Technical optimization refers to all the factors related to the technical details of your website, and how they affect the ranking of your site in search engines. They are important because they give valuable information to the spider that crawls your site, and ultimately decides how close to the top of a search you are placed. And this visibility directly impacts the traffic and profitability of your website.

Optimizing includes:

Keywords in your URL (optimal, but not always possible)

Keyword density of about 8% per page

Key phrases that relate to the keywords of very page

Keywords in titles and headings

Bold and capitalized words

Keywords in the first and last sentences of each page

Keywords and secondary keyword optimization on the site