FIFOs (First-In-First-Out) memory is a type of data storage device used to buffer data in digital systems. It stores data in a sequential manner, with the first data element written into the memory being the first to be read out. FIFOs help manage data flow between subsystems operating at different speeds or with asynchronous timing requirements. They are commonly used in communication interfaces, data processing systems, and digital signal processing applications to manage data transfer and mitigate timing issues.