Code execution refers to the process where a computer or device runs a set of instructions written in a programming language. This involves translating the code into machine language that the computer's processor can understand and execute. The execution can occur in various environments, such as local machines, servers, or cloud platforms. During code execution, the program performs tasks like calculations, data processing, or interacting with users. The efficiency and speed of execution can depend on factors like the programming language used, the complexity of the code, and the hardware capabilities of the device running it.