By Paul Bovbel
Udev is a device manager for Linux that dynamically creates and removes nodes for hardware devices. In short, it helps your computer find your robot easily. By default, hardware devices attached to your Linux (Ubuntu) PC will belong to the root user. This means that any programs (e.g. ROS nodes) running as an unpriveleged (i.e. not root) user will not be able to access them. On top of that, devices will receive names such as ttyACMx and ttyUSBx arbitrarily based on the order in which they were plugged in. Luckily, you can solve this, and more, with udev rules.