While doing the project, I met a little problem that was really annoying in fact.
I had to manipulate XML document dynamically that was done by PHP. Everything worked well, the new data were written down XML document. When I had loaded the data from the XML document into HTML document immediately after manipulating them, however, the problem appeared. The new data was not as I had desired, it was still the old data. I tried to refresh the XML document in browser and it worked, I got the desired result.
In this case, there is something happened when I had loaded the XML document so it is necessary to refresh the XML document in other to get the desired result.
The something that I mentioned above is caching or web cache.