systemvariabel

Systemvariabel, also known as system variables or environment variables, are dynamic named values that can affect the way running processes will behave on a computer. They are part of the operating system's environment and are accessible by programs. These variables are typically set when a user logs in or when the operating system starts up.

Common system variables include paths to executable files, the user's home directory, and system configuration settings. For instance, the PATH variable tells the operating system where to find executable programs when a command is entered without specifying its full path. Other variables might store information about the current user, the computer's name, or the operating system's version.

Programs can read these variables to adapt their behavior. For example, a program might check the TEMP variable to determine where to create temporary files. Developers often use system variables to configure applications without modifying their source code, making deployment and customization easier.

Changes to system variables can be made temporarily for a specific session or permanently for the entire system, depending on the operating system and the user's privileges. It is important to exercise caution when modifying system variables, as incorrect changes can lead to system instability or prevent programs from running correctly. Understanding system variables is fundamental for system administration, software development, and troubleshooting.