Why is my Nissan X-Trail's engine making strange noises?

I recently noticed that my Nissan X-Trail's engine is making strange noises. It's not a constant sound, but it happens intermittently and it's starting to worry me. It sounds like a ticking or knocking noise. What could be causing this and should I be concerned?

It's possible that your engine is low on oil. Check your oil levels and top up if necessary. Low oil levels can cause strange noises in the engine.