A "Black Project" refers to a classified military or government project that is not publicly acknowledged or disclosed. These projects often involve advanced technology, research, or operations that are kept secret for national security reasons. Examples can include experimental aircraft, weapons systems, or intelligence operations. Due to their secretive nature, Black Projects are often surrounded by speculation and conspiracy theories. They may involve significant funding and resources, typically sourced from government budgets that are not subject to public scrutiny. Notable examples include the development of the Lockheed SR-71 Blackbird and the B-2 Spirit stealth bomber.