The following is the Nov. 21, 2022, Congressional Research Service, Defense Primer: Special Operation Forces.
From the report
Special Operations Forces (SOF) are those active duty and reserve component forces of the military services designated by the Secretary of Defense (SECDEF) and specifically selected, organized, trained, and equipped to conduct and support special operations. Special operations frequently require unique modes of employment, tactics, techniques, procedures, and equipment....
https://news.usni.org/2022/11/22/defense-primer-u-s-special-operation-forces