What is debugging? 🐞

#programming #beginners #tutorial

Introduction 🐞

Programming is a complex process, and because it is done by human beings, it often leads to errors.
Programming errors are called bugs and the process of tracking them down and correcting them is called debugging.
Use of the term bug to describe small engineering difficulties dates back to at least 1889, when Thomas Edison had a bug with his phonograph.
Three kinds of errors can occur in a program: syntax errors, runtime errors, and semantic errors
It is useful to distinguish between them in order to track them down more quickly.

Python can only execute a program if the program is syntactically correct; otherwise, the process fails and returns an error message.
Syntax refers to the structure of a program and the rules about that structure.
For example, in English, a sentence must begin with a capital letter and end with a period. this sentence contains a syntax error. So does this one
For most readers, a few syntax errors are not a significant problem, which is why we can read the poetry of E. E. Cummings without problems.
Python is not so forgiving If there is a single syntax error anywhere in your program, Python will display an error message and quit, and you will not be able to run your program.
During the first few weeks of your programming career, you will probably spend a lot of time tracking down syntax errors.
As you gain experience, though, you will make fewer errors and find them faster.

The second type of error is a runtime error, so called because the error does not appear until you run the program.
These errors are also called exceptions because they usually indicate that something exceptional (and bad) has happened.

The third type of error is the semantic error.
If there is a semantic error in your program, it will run successfully, in the sense that the computer will not generate any error messages, but it will not do the right thing.
It will do something else specifically, it will do what you told it to do.
The problem is that the program you wrote is not the program you wanted to write.
The meaning of the program (its semantics) is wrong.
Identifying semantic errors can be tricky because it requires you to work backward by looking at the output of the program and trying to figure out what it is doing.