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What is Batch?

Windows batch files (.bat and .cmd) are script files executed by the Windows command interpreter (cmd.exe), with origins tracing back to MS-DOS in 1981 and the earlier CP/M operating system. Batch scripting provides a way to automate sequences of Windows commands, from simple file operations to complex deployment workflows involving conditional logic, loops, variable manipulation, and error handling. The language uses commands like ECHO, SET, IF, FOR, GOTO, CALL, and environment variable expansion (%VAR% and delayed !VAR!) to control execution flow.

Despite its age and well-known limitations — including inconsistent error handling, limited string manipulation, and counter-intuitive quoting rules — batch scripting remains deeply embedded in Windows system administration, enterprise IT operations, and legacy application deployment. Many organizations maintain critical batch scripts for automated backups, scheduled tasks, service management, network configuration, and software installation. Build systems for Windows-native applications frequently use batch files as entry points, and tools like Visual Studio's Developer Command Prompt rely on batch scripts to configure the environment.

The CMD shell processes batch files sequentially, with the ability to call subroutines and other batch files. While PowerShell has largely superseded batch for new automation tasks, the vast installed base of existing batch scripts — particularly in enterprise environments with long-lived Windows server infrastructure — ensures continued relevance. Modern Windows still ships cmd.exe and fully supports batch execution, maintaining backward compatibility with scripts written decades ago.