A 64-bit system refers to a computer architecture that uses 64 bits to represent data and memory addresses. This allows for a significantly larger amount of memory to be accessed compared to a 32-bit system, which can only address up to 4 GB of RAM. With a 64-bit system, the theoretical limit is 16 exabytes, enabling more efficient processing and multitasking capabilities. Most modern operating systems, such as Windows, macOS, and Linux, support 64-bit architecture, allowing users to run more demanding applications and handle larger datasets. Additionally, many software programs are now designed specifically for 64-bit systems, taking advantage of the increased performance and memory capacity.