Types of Errors

Types of error: An error is considered as a speed breaker in the process of program developing. This error may be of any type. There are four types of errors.

1) Syntax error, 2) Linking error, 3) Run Time error, 4) Logical error

Syntax error: This error occurs when the rule or syntax of the language is broken. Such errors may be of missing semi colon, missing of any punctuation, misuse of any term etc. For example: c = (a+b/2; Here in example, closing bracket is missing after b.

All syntax errors must be found and corrected before a program is made to run. Almost all the language compilers and interpreters are designed to detect syntax errors. The language processors print error messages on the screen that indicates the number of the statement with errors and gives hints of nature of the error.

Linking error: As we know that each language comes with built in libraries and basic functions. To execute a program we use these basic functions along with the libraries. It is the responsibility of the linker to link the function with the library. If the linker does not find the library then an error is generated. This error is known as linking error. For example: if main() method's library is not defined i.e. stdio.h

Runtime error: It is not sure that after successfully compiling and linking a program, it will display the desired result. The result may be wrong due to errors in logic such as division by zero, square root of a negative number. Runtime errors are harder to find and to correct them. It is because compiler does not tell us about the error. Compiler does not tell the number of line in which the occurred and also not the nature of the error.

Logic Errors: Logic errors are those that appear once the application is in use. They are most often unwanted or unexpected results in response to user actions. In this case the language processor successfully translates the source code into machine code. Also a computer actually does not know that an error has occurred. It follows the instructions and produces the results, but this output may be wrong. For example, a mistyped key or other outside influence might cause your application to stop working. Logic errors are generally the hardest type to fix, since it is not always clear where they originate.