Free Software Foundation provides short summaries of the key open source licenses, including whether the license qualifies as a free software license or a copyleft license.  Also includes a discussion of what constitutes a free software license or a copyleft license (e.g., a Copyleft license is a general method for making a program or other work free, and requiring all modified and extended versions of the program to be free as well.)
Free Software Foundation provides short summaries of the key open source licences, including whether the licence qualifies as a free software licence or a copyleft licence.  Also includes a discussion of what constitutes a free software licence or a copyleft licence (e.g., a Copyleft licence is a general method for making a program or other work free, and requiring all modified and extended versions of the program to be free as well.)