Skimming and scanning are two reading techniques used to obtain information from text quickly. Skimming is used to get the overall idea or main points of a text, while scanning is used to find specific information within a text. The document provides tips for how to skim, such as reading titles, subtitles, and first/last sentences of paragraphs. It also provides tips for scanning, such as not reading every word but letting your eyes move quickly while using clues like headings to find what you're looking for. Both skimming and scanning are useful techniques for studying or finding information efficiently.