Final answer:
The system used to classify bacteria into different types is based on various traits, including differences in their cell walls and outer membranes. One classification is based on Gram stain reaction.
Step-by-step explanation:
The system used to classify bacteria into different types is based on various traits, including differences in their cell walls and outer membranes. One classification is based on Gram stain reaction, which involves staining bacteria with a dye to determine whether they are Gram-positive or Gram-negative. Gram-positive bacteria retain the purple stain, while Gram-negative bacteria take on a pink color.