The short answer
With a GRBL diode laser and a tight budget, try Rayforge first: it is free, runs on Linux, Windows and macOS, and has camera alignment. If you run a Ruida CO2 or a galvo laser, or want the largest community and most tutorials, LightBurn is the safer choice, in its Pro edition for those controllers. On Linux, Rayforge has the edge, because LightBurn 1.7 is its final Linux version.
- GRBL on a budget → Rayforge
- Ruida or galvo → LightBurn Pro
- Linux → Rayforge
- Most tutorials and community → LightBurn