When looking at different chemicals, I come across the 'preferred IUPAC name' and the 'systematic IUPAC name'. I've noticed that when I name chemicals, I name them by their 'systematic IUPAC name', as I've been taught to name them using this system.
When is the 'preferred IUPAC name' used? I sometimes come across it when looking at aldehydes, ketones and carboxylic acids. However, the fact that it's 'preferred' makes me wonder whether chemists use this method more often than the other system.