Twitter has announced a new tool that permits users to identify information they believe is false or misleading. The program is called Birdwatch. Twitter is first testing the program with a small group of approved users in the United States. The users will be able to write notes about tweets they consider untrue or that may contain misinformation. In an announcement about the tool on Tuesday, Twitter said in the future, it plans to make the system available to all its users worldwide. The program aims to have both experts and non-experts write notes. Twitter said in a statement that tests it carried out in the past had showed that non-experts write concise, helpful and easy-to-understand notes. Such notes were often supported with “valuable expert sources, it added.