Keywords are the search terms that people into search engines. Your rankings are based on the relevance of your page to those keywords.
Web analytics is the measurement, collection, analysis and reporting of web data for purposes of under standing and optimizing web usage.
Email marketing is directly sending a commercial message, typically to a group of people, using email. In its broadest sense, every email.
SEO stands for “search engine optimization.” It is the process of getting traffic from the “free,” “organic,” “editorial” or “natural” search results on search engines.