Equal-area refers to a property of certain maps or projections where areas on the map are proportional to the areas on the Earth's surface. This means that if two regions are represented on the map, their sizes will accurately reflect their actual sizes in reality. This is particularly useful for comparing the size of different geographical areas. Common examples of equal-area projections include the Albers Equal-Area Conic and the Mollweide projection. These projections are often used in thematic maps, where accurate area representation is crucial for understanding data related to population, land use, or natural resources.