As large language models (LLMs) gain increasing attention for real-world applications, research is increasingly focusing on automating workflows through the use of agents. This presentation provides an overview of fundamental concepts related to autonomous agents and introduces a line of research that leverages LLMs for designing agents capable of real-world tasks. We discuss both classical and modern approaches to agent design and compare them to illustrate how LLMs can enhance agents' decision-making processes. Finally, we present our research on an agent system where agents engage in conversations, with their self-emotions being simulated through a series of events. Additionally, we report how these simulated emotions influence the agents' dialogue behaviors in both dyadic conversations and group discussions.