Terms you should know: SERP - search engine results page ROI - return on investment USP - unique selling proposition CTR - click-through ratio CPM - cost per thousand (impressions) PPC - pay per click widget - a hypothetical product conversion ratio - a percentage of leads that perform a desired action (sign-up, sale) attribute - a specific visual or conceptual element of a page, an ad creative, or a sales letter (used in fine-grained performance...