Multithreading and concurrency are essential concepts in computer science that enable efficient execution of multiple tasks simultaneously. Multithreading refers to the ability of a program to manage multiple threads, which are smaller units of a process, allowing for parallel execution of tasks. This enhances CPU utilization and improves application performance. Concurrency, on the other hand, is the broader concept of managing multiple tasks at the same time, which can occur through multithreading or other methods. Understanding these concepts is crucial for developing responsive applications that can handle various operations without delays, ultimately leading to a better user experience.