Google AdWords is Google's main advertising product and main source of revenue. Google's total advertising revenues were USD$28 billion in 2010. AdWords offers pay-per-click, i.e, cost-per-click (CPC) advertising, cost-per-thousand-impressions or cost-per-mile (CPM) advertising, and site-targeted advertising for text, banner, and rich-media ads. The AdWords program includes local, national, and international distribution. Google's text advertisements are short, consisting of one headline consisting of 25 characters and two additional text lines consisting of 35 characters each. Image ads can be one of several different Interactive Advertising Bureau (IAB) standard sizes.
PHP is a widely-used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML.
Free and open source software (F/OSS, FOSS) or free/libre/open source software (FLOSS) is software that is both free software and open source. It is liberally licensed to grant users the right to use, copy, study, change, and improve its design through the availability of its source code.