The main difference is control.

Clone Stamp lets you choose the source area yourself and manually paint pixels from that spot onto another area. That gives you fine control over exactly what gets copied, which is helpful in difficult edits or when you need precision.

Content-Aware Fill is more automatic. Photoshop analyzes the surrounding image and tries to generate a believable fill on its own. It’s usually faster when it works well, especially for simple distractions against fairly consistent backgrounds.

In practice:

• Use content-aware when you want a quick automatic removal and the surrounding area is simple or repetitive.
• Use clone stamp when the automatic result fails, or when you need careful control over texture, edges, or specific details.

Neither is always better. Content-aware is often faster; Clone Stamp is often more reliable for complex situations because you decide the source.