A permissive open source licence also known as the X11 Licence. Although the wording is quite different in parts, it is functionally very similar to the various BSD style licences such as the Three Clause BSD Licence but in general if you are considering such a license for a new project the ISC Licence is clearer and therefore recommended.
Note that the licence text below is here for reference purposes and unlike other material on the EDM/2 Wiki is not under the Attribution-ShareAlike 3.0 licence and should be treated under its own terms, or if an addition by the combined terms of the addition and the licence that it is an addition to. As it is a licence with fixed terms the text below it should not be modified except for formatting purposes, if a more recent version is published a new page should be created for that licence since software packages that do not get updated will continue to be governed by the terms of the older licence.
Text of licence
Copyright (c) <year> <copyright holders>
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.