What is the default behavior of Karel when it encounters an obstacle?

When Karel encounters an obstacle, the default behavior is to halt its movement forward, which aligns with the understanding that Karel is limited by its immediate environment. In programming terms, this is often defined by the presence of wall blocks or barriers that Karel is programmed not to move through.

The design of Karel emphasizes a simplified model of robotics where collision detection is fundamental. Instead of attempting to navigate around obstacles or producing error messages, Karel remains stationary until further commands are issued, effectively ensuring that it does not breach any defined boundaries. This allows for clear and predictable programming that reinforces foundational coding concepts.