Protected areas or conservation areas are locations which receive protection because of their recognized natural, ecological or cultural values. There are several kinds of protected areas, which vary by level of protection depending on the enabling laws of each country or the regulations of the international organizations involved. Generally speaking though, protected areas are understood to be those in which human presence or at least the exploitation of natural resources (e.g. firewood, non-timber forest products, water, ...) is limited.

The term "protected area" also includes marine protected areas, the boundaries of which will include some area of ocean, and transboundary protected areas that overlap multiple countries which remove the borders inside the area for conservation and economic purposes. There are over 161,000 protected areas in the world (as of October 2010) with more added daily, representing between 10 and 15 percent of the world's land surface area.

As of 2016, there are 14,688 Marine Protected Areas (MPAs), and approximately 14.7% of the world's terrestrial and inland water areas (excluding Antarctica) are protected. For waters under national jurisdiction beyond inland waters, approximately 10.2% of coastal and marine areas and 4.12% of global ocean areas are covered by marine protected areas. In contrast, only 0.25% of the world's oceans beyond national jurisdiction are covered by MPAs. As of December 2022, 17% of land and 10% of ocean territory were protected.

In recent years, the 30 by 30 initiative has targeted to protect 30% of ocean territory and 30% of land territory worldwide by 2030; this has been adopted by the European Union in its Biodiversity Strategy for 2030, Campaign for Nature which promoted the goal during the Convention on Biodiversity's COP15 Summit and the G7. In December 2022, Nations have reached an agreement with the Kunming-Montreal Global Biodiversity Framework at the COP15, which includes the 30 by 30 initiative.

Protected areas are implemented for biodiversity conservation, often providing habitat and protection from hunting for threatened and endangered species. Protection helps maintain ecological processes that cannot survive in most intensely managed landscapes and seascapes.