Ecosystem services are the many and varied benefits to humans provided by the natural environment and healthy ecosystems. Such ecosystems include, for example, agroecosystems, forest ecosystem, grassland ecosystems, and aquatic ecosystems. These ecosystems, functioning in healthy relationships, offer such things as natural pollination of crops, clean air, extreme weather mitigation, and human mental and physical well-being. Collectively, these benefits are becoming known as ecosystem services, and are often integral to the provision of food, the provisioning of clean drinking water, the decomposition of wastes, and the resilience and productivity of food ecosystems. While scientists and environmentalists have discussed ecosystem services implicitly for decades, the Millennium Ecosystem Assessment (MA) in the early 2000s popularized this concept. There, ecosystem services are grouped into four broad categories: provisioning, such as the production of food and water; regulating, such as the control of climate and disease; supporting, such as nutrient cycles and oxygen production; and cultural, such as spiritual and recreational benefits. To help inform decision-makers, many ecosystem services are being evaluated to draw equivalent comparisons to human-engineered infrastructure and services. Estuarine and coastal ecosystems are both marine ecosystems. Together, these ecosystems perform the four categories of ecosystem services in a variety of ways: "Regulating services" include climate regulation as well as waste treatment and disease regulation and buffer zones. The "provisioning services" include forest products such as timbers, marine products fresh water, raw materials, and biochemical and genetic resources. "Cultural services" of coastal ecosystems include inspirational aspects, recreation and tourism, science and education. "Supporting services" of coastal ecosystems include nutrient cycling, biologically mediated habitats, and primary production. Definition Ecosystem services or ‘eco-services’ are defined as the goods and services provided by ecosystems to humans. Per the 2006 Millennium Ecosystem Assessment (MA), ecosystem services are "the benefits people obtain from ecosystems". The MA also delineated the four categories of ecosystem services—supporting, provisioning, regulating, and cultural—discussed below. In simple terms provision of food materials, water, timber, fibers, and the provision of medications. By 2010, there had evolved various working definitions and descriptions of ecosystem services in the literature. To prevent double-counting in ecosystem services audits, for instance, The Economics of Ecosystems and Biodiversity (TEEB) replaced "Supporting Services" in the MA with "Habitat Services" and "ecosystem functions", defined as "a subset of the interactions between ecosystem structure and processes that underpin the capacity of an ecosystem to provide goods and services". Categories Four different types of