Evolution of Artificial Intelligence Models and Agents: A Survey and Future Research Directions

Artificial Intelligence (AI) is all about building the systems that can observe the world carefully,think about it, learn through experience and completely the task accurately. In the last decade, progress in data, computing power and neural network architectures has produced powerful AI models, especially deep learning systems, transformers and large language models (LLMs). Building on these models, a new class of systems called AI agents can pursue goals autonomously by planning, using tools, remembering context and acting on their environment. This paper reviews the foundations of AI, the major types of AI models, the architecture and types of AI agents, their applications across sectors, and the challenges of safety, bias, privacy and governance that accompany them.