Since the Administrative Procedure Act (c. 324, 80 Stat. 237 (1946)) was passed, most federal regulations must be created by a process called "notice and comment." This means that when a regulation is being created, public notice must be given. This notice must include the proposed text of the regulation. The comment portion requires agencies to allow the public to participate in the creation of regulations by giving them the ability to express their opinion about the regulation to the agency.
Glossary at Regulations.gov: definitions of rulemaking terminology.
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