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 32-bit systems, which can only address up to 4 GB of RAM. With a 64-bit system, the theoretical limit is 16 exabytes, although practical limits are much lower due to hardware and operating system constraints. Most modern operating systems, such as Windows, macOS, and Linux, support 64-bit processing, enabling them to run more efficiently and handle larger applications. Additionally, software designed for 64-bit systems can take advantage of improved performance and security features, making them suitable for demanding tasks like gaming, video editing, and data analysis.