For example, in the United States, the copyright protection for musical compositions created on or after January 1, 1978, lasts for the life of the composer plus 70 years. This means that a song written by a composer who died in 1950 would enter the public domain in the United States in 2021, 70 years after the composer's death.
However, there are some exceptions to these general rules. For example, in the United States, songs created before January 1, 1978, are protected by copyright for a term of 95 years from the date of publication, or 120 years from the date of creation, whichever is shorter.
Additionally, some countries have provisions for "moral rights" that give authors certain rights over their works even after they have entered the public domain. For example, in some countries, authors may have the right to prevent their works from being modified or distorted in a way that is prejudicial to their reputation.