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Every programmer makes mistakes and most make mistakes every day.

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Although good programmers might create errors and they also know how to respond to these errors efficiently.

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Now let's look at an error you will likely to make early on and learn how to fix it.

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So we will write some code that generates an error on purpose and enter the this code here.

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Message.

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Message here and we will write.

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Hello.

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By then.

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Parash.

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Or Python.

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After that, we will print message.

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So if an error occurs in your program, the Python interpreter does its best to help you figure out

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where the problem is.

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So the interpreter provides a traceback when a program cannot run successfully.

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Here.

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That's it.

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It's actually widen it a little bit.

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The traceback is a record of where the interpreter ran into trouble when trying to execute your code.

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Here's an example of the traceback that Python provides after you have accidentally misspelled a variable's

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name.

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Here.

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Let's actually use this marker.

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Yes.

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So here, this is our first line, right?

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This is our first line that Python gave us.

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So here we have error.

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And we also have print function names and name message is not defined.

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So here.

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The output reports that an error occurs in line two.

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Here.

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Error occurs in line two of the main dot pi.

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Python file and the interpreter shows this line.

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To help us to stop the error quickly and tells us what kind of error it found.

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In this case, it found the name error and reports that the variable being printed message has not been

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defined and Python cannot identify the variable name provided.

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A name error usually means we either forgot to set a variable's value before using it or we made a spelling

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mistake when entering the variables name.

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If Python finds a variable name that's similar to one it doesn't recognize, it will ask if that's the

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name you meant to use.

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In this example we omitted the letter s in the variable name message in the second line and the python

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interpreter doesn't spell check your code, but it does ensure that the variable names are spelled consistently.

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So, for example, watch what happens when we spell the message incorrectly in the line that defines

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the variable.

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Let's actually make this.

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That's it.

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In this case, the program runs successfully the variable name match.

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So Python sees no easy programming language are very strict, but they disregard good and bad spelling.

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As a result, you don't need to consider English spelling and grammar rules when you are trying to create

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a variable names and writing code.

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So many programming errors are simple single character typos in one line of program.

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If you find yourself spending a lot of time searching for one of these errors, know that you are in

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a good company.

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So many experienced and talented programmers spent hours hunting down these kinds of tiny errors.

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Try to laugh about it and move on, knowing it will happen frequently throughout your programming live.