I have always been interested in do it yourself plans and worked upon searching for these. Before the internet was commonly used, I searched books and magazines for the same. I discovered many copies of old magazines like Mechanix Illustrated, Science and Mechanics and many others of the kind offered lots of such do it yourself plans. The internet definitely made things much easier and quicker and helped in clearing many doubts about copyrighted works.After having worked upon hundreds of such articles, I discovered that articles with expired copyright entered a “public domain” and was accessible by anyone for any purpose; no one could claim any copyright infringement on these works. All materials published in the United States between 1923 and 1964 were issued a 28 year copyright which had to be renewed in the 28th year. If this was not done prior to the expiry date, the project entered the public domain and its copyright could not be refreshed. Any work that was published before 1923 has now automatically entered the public domain without any exceptions. In 1964, copyright laws were changed and works registered in this year were copyrighted for a much longer time. However, in certain cases, publications up to 1978 are found in the public domain.An expired copyright invites all kinds of infringement and plagiarism. Anyone can use this work at any time for any work. This does not only include printed material but also audios and videos. These projects can be reproduced, reprinted, exhibited, broadcasted, or altered.Anyone willing to claim copyrights over a public domain item must change it considerably and then apply for the authority of its rights. The project in the original form has been accepted as a copyright expired material therefore, it cannot be registered after the expiry date.When copying another author’s piece, you must be very careful of his moral and legal rights or your work will be accused of copyright violation. Works dating back to before 1923 are definitely, without any doubt, in the public domain and there is no objection in reproducing it. Any project that interests you and was published between 1923 and 1964 will most probably be in the public domain but its status should be confirmed by checking records at the United States Copyright Office. This can more conveniently be done online. Works dating back to even before 1928 can also be found on many website, is one of the examples.