Axion and Axion-Like Particle Dark Matter

One very compelling dark matter candidate is the ALP, or axion-like particle. These particles generically are expected to have extraordinarily feeble interactions with normal matter and radiation, have very low masses and long lifetimes, and would be produced non-thermally in the early universe. Like their WIMP dark-matter counterparts, they arose as a solution to problems in the Standard Model, and their properties make them ideal dark-matter candidates. Large and ultra-sensitive experiments are now being deployed which are finally able to detect these particles or rule them out at high confidence. This talk will review this attractive dark-matter candidate and the status of the various searches.