First, we need to ask ourselves why we should bother choosing a license?
- presenting your software to the public?
- representing your software in a way that leads others to believe they can copy it or build on it?
Then, yes, you should choose a license. Be fair to your visitors and back up the appearance of permission by expressly giving permission.
The copyright law defaults to author control of copying, modification, and distribution, so others need the author’s permission to copy, modify, or distribute. If you would like others to be free to copy your software and possibly build on it, then you should choose a license. Open source licenses give the permissions needed to get that default copyright impediment out of the way.
Read more at OpenSource.com