Description: An executable is a file that contains instructions that a computer can directly execute as a program. In the context of operating systems, executable files are essential for the system’s functioning, as they allow users and programs to perform specific tasks. These files can be scripts, compiled programs, or any other type of file that the operating system recognizes as executable. For a file to be considered executable in a Unix-like operating system, it must have the appropriate permissions, which can be checked and modified using commands like ‘chmod’. Executables are fundamental in system administration, task automation, and software development, as they enable users to run applications and scripts efficiently. Additionally, executables can be used in combination with other command-line commands and tools to create more complex and customized workflows.
History: The concept of executable files dates back to the early days of computing when operating systems began allowing programs to be executed from disk. In Unix-like systems, which emerged in the 1970s, file permissions were introduced, allowing users to define which files could be executable. Over time, the executable file format was standardized, and in many Unix-like systems, executable files typically have the ‘.out’ extension or no extension at all. The evolution of operating systems and programming has led to the creation of various tools and languages that facilitate the creation and management of executable files.
Uses: Executable files are used in a variety of contexts within operating systems. They are essential for running applications, automation scripts, and system administration tools. System administrators use executables to perform routine tasks such as backups, software updates, and system monitoring. Additionally, software developers create executables to distribute their applications to end users. Scripts, which are text files containing shell commands, are a common form of executables, allowing users to automate complex tasks easily.
Examples: An example of an executable file is a script that automates file backup. This script can be created by a user and then executed from the command line. Another example is a compiled C program that has been turned into an executable file using a compiler. Users can run this program directly from the command line. Additionally, many software programs, such as text editors and web browsers, are distributed as executable files that users can install and run on their systems.
