Program Debugging: Syntax Errors vs. Semantic Errors

• Program Debugging:
  • The process of finding and correcting errors (bugs) in a computer program is called program debugging.
  • Errors are inevitable during program development.

Syntax Errors:

• Syntax errors are caused by invalid syntax, such as typing prnt instead of print.
• Translators (compilers or interpreters) cannot understand instructions that contain syntax errors.
• As a result, translators terminate when encountering syntax errors and indicate where in the program the problem occurred.
• For example, a misspelling of a keyword or the omission of necessary punctuation marks can cause syntax errors.

Semantic Errors (Logic Errors)

• Semantic errors, also known as logic errors, are caused by errors in program logic.
• Translators cannot automatically detect these errors because they cannot understand the intent behind the computation.
• For example, if a program calculates the average of three numbers using (num1 + num2 + num3) / 2.0 instead of dividing by 3, a translator would not recognize this mistake.
• Computers only follow the given instructions and do not understand what the program is meant to do. Therefore, it is up to the programmer to detect and correct these errors.