I hear this cry all the time. You have slaved over your post, updated it, or made changes to it, but when you preview it, you still see the same old post or page.
It is your browser. Firefox, IE, (internet explorer), Safari or Chrome. They all have the same problem.
Why clearing or refreshing your browser cache?
How this effects us and our updates and changes.
Most of us spend a lot of time on on our own websites. Checking things and looking at how things are doing.
So your browser is going to have lots of cached pages you have looked at.
So when you make those changes, they are there, but your browser is showing you the old version, since it has it saved in the cache.
How to refresh Browsers and see your updates | WordPress
If you are on a PC.
Hold down Ctrl (short for control), and the F5 button. Sometimes you can just hit the F5 key by itself and it will work. So try that on your computer and see if you need to use Ctrl and F5.
If you are on a Mac , you will need to click the little refresh icon in the url address window. Or you can do a force refresh which is hold down the Command key and the R key.
Some helpful links on how to clear your cache.