Search Engine Optimization (often abbreviated "SEO") refers to steps taken to make a website easy for search engines to understand and to value highly. These optimization techniques are roughly divided into two types: on-page and off-page.
On-page techniques include assuring that there is a title that reflects what the page is about, that the code on the page is compliant with HTML and other standards, and that the term you want the page to rank well for is featured prominently on the page.
Off-page techniques refer to linking to the page from other web pages, on the same site or on other sites. Links from social media sites are particularly important in off-page optimization.
A closely related term is "Search Engine Marketing", which refers to the practice of SEO for the purpose of using listings in search engine results pages for marketing products and services.
A Solo Ad is an ad sent in your behalf by the owner of a mailing list.
Creating multiple versions of the same text through the use of synonym replacement