Large language models have revolutionized the way humans interact with AI systems, transforming a wide range of applications and disciplines. In this talk, we discuss several approaches to enhancing human-AI and AI-AI interactions using LLMs. The first one explores how large language models transform computational social science, and how human-AI collaboration can reduce costs and improve the efficiency of social science research. We then introduce efficient machine unlearning techniques to enable LLMs to forget sensitive user data if needed, towards secure and responsible interaction. The last part looks at AI-AI interaction via a dynamic LLM agent network for multi-agent collaboration on complicated reasoning and generation tasks. We conclude by discussing how LLMs enable collaborative intelligence by redefining the interactions between humans and AI systems.