This colloquium explores phononics, the manipulation of heat flow using electronic analogs and beyond. The authors present theoretical and experimental concepts for phononic devices, including thermal diodes, transistors, logic gates, and memories, which enable controlled heat transport and information processing. The key idea is that phonons, the quasiparticles responsible for heat, can be manipulated similarly to electrons and photons, allowing for the development of phononic technologies. The paper discusses the use of asymmetric nanostructures to achieve thermal rectification, where heat flows more easily in one direction than the other. This is demonstrated through various models, including nonlinear lattice structures and carbon nanotubes. The authors also explore the role of negative differential thermal resistance (NDTR), which allows for the amplification and control of heat flow, similar to electronic transistors. Thermal transistors are proposed as devices that can switch and amplify heat, enabling more complex information processing. Thermal logic gates are also discussed, where heat is used to perform logical operations. These gates rely on the NDTR phenomenon and can function as switches or modulators. The paper further presents thermal memory elements, which can store information by encoding it in heat or temperature. These memories exhibit stable states that can be read and written, making them suitable for information storage. The authors also highlight the potential of phononics in various applications, such as thermal rectification in nanoscale systems, heat shuttling, and the topological phonon Hall effect. They emphasize the importance of combining theoretical models with experimental validation to advance phononic technologies. The paper concludes with a discussion of future prospects, challenges, and the potential of phononics to revolutionize energy transport and information processing.This colloquium explores phononics, the manipulation of heat flow using electronic analogs and beyond. The authors present theoretical and experimental concepts for phononic devices, including thermal diodes, transistors, logic gates, and memories, which enable controlled heat transport and information processing. The key idea is that phonons, the quasiparticles responsible for heat, can be manipulated similarly to electrons and photons, allowing for the development of phononic technologies. The paper discusses the use of asymmetric nanostructures to achieve thermal rectification, where heat flows more easily in one direction than the other. This is demonstrated through various models, including nonlinear lattice structures and carbon nanotubes. The authors also explore the role of negative differential thermal resistance (NDTR), which allows for the amplification and control of heat flow, similar to electronic transistors. Thermal transistors are proposed as devices that can switch and amplify heat, enabling more complex information processing. Thermal logic gates are also discussed, where heat is used to perform logical operations. These gates rely on the NDTR phenomenon and can function as switches or modulators. The paper further presents thermal memory elements, which can store information by encoding it in heat or temperature. These memories exhibit stable states that can be read and written, making them suitable for information storage. The authors also highlight the potential of phononics in various applications, such as thermal rectification in nanoscale systems, heat shuttling, and the topological phonon Hall effect. They emphasize the importance of combining theoretical models with experimental validation to advance phononic technologies. The paper concludes with a discussion of future prospects, challenges, and the potential of phononics to revolutionize energy transport and information processing.