Changed how?
- Are you loading externally?
- Is it already loaded but hidden?
- What exactly is the content anyway? Do you want to show text, an image, a page, a frame, a series of elements?
- What is the expected behavior exactly? As in...
- When you click the link is it loading externally (as mentioned first) or is it loading another page via pushState?
- etc etc
You gotta be way more specific, without even know what your expected behaviour is, I cannot even point you toward tutorials about it, but they abound no matter what it is you're trying to do.
Dynamic content means that it's not from static HTML files, so changing dynamic content could mean loading via AJAX, loading via AJAX and using pushState, loading in an iframe (for time travellers), etc etc