"80%" refers to a proportion or percentage that represents four-fifths of a whole. In numerical terms, it is equivalent to 0.8 when expressed as a decimal. This percentage is often used in various contexts, such as statistics, finance, and everyday situations, to indicate a significant majority or a large portion of a total. For example, if a survey shows that 80% of respondents prefer a certain product, it means that out of every 100 people surveyed, 80 chose that product over others. This concept helps in understanding trends, making decisions, and analyzing data effectively.