ThinkPHP遵循Apache2开源协议发布，并提供免费使用。
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All rights reserved。
ThinkPHP® 商标和著作权所有者为上海顶想信息科技有限公司。
Apache Licence是著名的非盈利开源组织Apache采用的协议。
该协议和BSD类似，鼓励代码共享和尊重原作者的著作权，
允许代码修改，再作为开源或商业软件发布。需要满足
的条件：
1． 需要给代码的用户一份Apache Licence ；
2． 如果你修改了代码，需要在被修改的文件中说明；
3． 在延伸的代码中（修改和有源代码衍生的代码中）需要
带有原来代码中的协议，商标，专利声明和其他原来作者规
定需要包含的说明；
4． 如果再发布的产品中包含一个Notice文件，则在Notice文
件中需要带有本协议内容。你可以在Notice中增加自己的
许可，但不可以表现为对Apache Licence构成更改。
具体的协议参考：http://www.apache.org/licenses/LICENSE-2.0
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
