From the Document: "Advanced technology plays a critical role in ensuring U.S. national security. To maintain technological superiority on the battlefield, the Department of Defense (DOD) relies on scientific and technical knowledge developed in large measure through research, development, test, and evaluation (RDT&E) funded by the department and performed by industry, universities, federal laboratories, and others. DOD also relies increasingly on technology developed by the private sector for commercial markets. This In Focus describes DOD's RDT&E appropriations structure and funding levels. DOD appropriations are provided annually through the defense appropriations act, one of the 12 regular appropriations acts. DOD RDT&E funding is generally provided in three of this act's titles (see box). Congress also sometimes provides DOD RDT&E funding through supplemental appropriations acts. DOD reports FY2021 total obligational authority (enacted) of $110.8 billion."
CRS In Focus, IF10553
Congressional Research Service: https://crsreports.congress.gov/