What is the difference between API3 and Chainlink?

As a crypto enthusiast, I'm curious to understand the key distinctions between API3 and Chainlink. Could you elaborate on the fundamental differences in their architectures, functionalities, and potential applications? Specifically, how do they approach the provision of decentralized APIs, and what are the key factors that set them apart in terms of scalability, security, and ease of integration? I'm also interested in hearing about their respective market positions, as well as any potential synergies or areas of competition between the two projects.