For the purpose of this book, consider artificial intelligence (AI) as the field of computer science responsible for making agents (software/robots) that act to solve a specific problem. In this case, "intelligent" means that the agent is flexible and it perceives its environment through sensors and will take actions that maximize its chances to succeed at some particular goal.
We want an AI to maximize something that is named Expected Utility or the probability of getting some sort of satisfaction by doing an action. An easy to understand example of this is by going to school, you will maximize your expected utility of getting a job.
AI aspires to replace the error-prone human intelligence involved in completing tedious everyday tasks. Some central components of human intelligence that AI aims to mimic (and an intelligent agent should have) are: