The Java Date and Time API is a set of classes introduced in Java 8 to handle date and time more effectively. It provides a comprehensive framework for managing dates, times, durations, and time zones, making it easier to perform date-related calculations and formatting. The API is designed to be immutable and thread-safe, which enhances reliability in multi-threaded applications. Key components of the API include LocalDate, LocalTime, and ZonedDateTime, each serving specific purposes. For instance, LocalDate represents a date without time, while ZonedDateTime includes time zone information. This structured approach simplifies date and time manipulation in Java applications.