What does a 4% yield mean?

Can you clarify for me what exactly a 4% yield represents in the context of cryptocurrency and finance? Is it referring to the annual return on an investment, such as in a savings account or a bond? Or does it have a different meaning in the world of crypto, perhaps related to staking rewards, lending platforms, or some other aspect of decentralized finance? Understanding the specifics of this term will help me make informed decisions when navigating the cryptocurrency landscape.