What type of errors occurs when the program is asked to implement an impossible task such as dividing a number by zero?

Programming errors are generally grouped into three categories: syntax errors, runtime errors, and logical errors. Each occurs at a different stage of running a program.

• Syntax errors happen when code breaks the grammar rules of the programming language (for example, a missing bracket or semicolon), and they are caught before the program even runs.
• Runtime errors happen while the program is actually executing, when it is asked to carry out an operation that is impossible or invalid during that execution, such as dividing a number by zero, accessing a file that does not exist, or running out of memory.
• Logical errors occur when a program runs without crashing but produces the wrong result because of a flaw in the reasoning or algorithm used.

Dividing by zero is mathematically undefined, so when a running program attempts it, the system halts that operation and reports the failure while the program is in progress. This mid-execution failure on an impossible task is the defining feature of a runtime error.

Exam tip: if an error happens only when the program is actually running and involves an operation that cannot be completed (like division by zero or a missing file), classify it as a runtime error rather than a syntax or logical error.