8 Different Types of Errors in Programming

Whether you’re already a professional or just starting a career in this field, chances are high you will come across plenty of errors throughout your programming process, which you will unquestionably need to fix in order to produce a quality end-product.

And while beginners might find themselves battling more errors than programmers with years of experience, mistakes are still a natural aspect of all human beings, no matter how proficient, and are bound to happen in your work as well. This is simply the nature of programming, and locating and fixing all the possible errors within your software might turn out to be one of the most difficult aspects of the job.

To that end, it might be wise to familiarize yourself with the possible programming error types you might encounter along the way, as well as ways you could discover and solve them, in order to become a better, more efficient programmer. So, here is a guide detailing everything you should know about programming errors:

What exactly are errors in programming?

Programming errors represent the faults or the mistakes that prevent the software from performing in the predicted, desirable manner. From smaller mistakes, such as mistyped code, to more challenging faults, like unexpected performance results or even sudden crashes, programming errors can manifest themselves in a number of different ways.

The errors which occur during coding are generally referred to as bugs, regardless of their nature, and the procedure of locating and solving any potential errors is known as debugging.

The most typical forms of programming errors

There are a wide variety of errors and other bugs that can be found during the coding process. However, there are certain mistakes that tend to happen more often, which most programmers have encountered at least once in their career. Here are just a few of the most typical issues you might notice as well:

1. Syntax error

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It’s a well-known fact that computer languages have their own set of grammar rules, much like our human languages do. But even though we have the ability to communicate even with imperfect grammar, computers aren’t quite as sophisticated.

This is exactly where syntax errors come in; they happen when a specific sequence of computer language rules isn’t followed exactly. In other words, syntax errors tend to be quite small mistakes that represent missing characters or misspelled words within the code, for instance.

While these forms of errors should become less common with practice, they always need to be fixed before your program can run. Thankfully, syntax errors should easily come up during the runtime.

2. Logical error

Also known as semantic errors, logical errors happen when a mistake within the program statements sequence occurs, such as the use of an incorrect function or formula.

Unfortunately, these errors can be particularly difficult to detect, as your program won’t crash or cause any serious issues. The program will technically be working properly, but it will produce a different result from the one that was expected. For this reason, a logical error might “make sense” to the programming language, even though it doesn’t fit properly into the program itself.

It might be a good idea to consult product managers when compiling tests in an effort to avoid making logical errors.

3. Arithmetic error

Although technically a logical error, arithmetic mistakes actually involve mathematics. They most commonly happen when a program attempts to perform an impossible task, such as the division by zero, often without the programmer even realizing it.

While these types of mistakes don’t necessarily seem so serious at first, they can quite often cause further logical errors, or even runtime errors when the division by zero is attempted. However, an arithmetic error could easily be prevented, as long as you have efficient tests that involve edge cases, such as negative numbers and zero.

4. Runtime error

As their name suggests, a runtime error is the one that occurs unexpectedly when your software is executed, or while it’s running. They are most likely the cause of any unpredicted events, such as out-of-range array elements or division by zero.

Runtime errors tend to be quite challenging to detect as well, as the software will most likely work well on your end, and the compiler won’t flag any abnormalities. However, they do present a more serious issue, as they affect the end-user, and block them from completing necessary tasks.

In an effort to prevent this kind of error, ensure you have an efficient error reporting system set in place, which will be able to notice possible runtime errors and open any potential bugs in the ticketing system automatically. Don’t forget to learn from these mistakes, in order to prevent repeating them in the future.

5. Resource error

The device where the software is currently running will always allocate a certain number of resources to it. In case an unpredicted aspect of the code prompts the device to attempt to assign more resources than it actually has, this will likely lead to resource errors.

Unfortunately, this kind of issue could be quite difficult to locate, as your device might be of better quality and have higher performance than the servers which are executing the code. What’s more, mimicking real-life use from a local device is also quite challenging.

In an effort to avoid resource errors, having a great reporting system of resource usage can be of great help. Either way, these issues could be more suited for the operations squad to correct, instead of developers.

6. Compilation error

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The programming language you use might call for compilation, which means that a code of a higher level needs to be translated into a code of a lower lever which should be simpler for the device to understand and process. When your compiler doesn’t possess the option to transform your algorithm into a language of lower-level correctly, that is when compilation (also known as compile-time) errors occur.

In case your program is experiencing these issues, you most likely won’t manage to perform tests or even launch it. However, you might manage to avoid compilation issues if you attempt to receive feedback early on. If you start the compiler more often, you should have the opportunity to get feedback every step of the way, allowing you to solve smaller issues as you go, instead of having to troubleshoot the entire software once you finish.

7. Interface error

When there happens to be a disparity between the intended usage of your software and the way it is currently utilized, interface errors will likely happen. As most programs tend to follow certain standards, interface errors could show up whenever the input that your software receives doesn’t adhere to the exact standards that you’ve set.

These errors could be particularly tricky to discern, as they might often appear as issues on your end, instead of mistakes on the end-user’s side. The most efficient way to deal with any interface errors is to have straightforward and comprehensible documentation, and locate these issues on time, in order to give your users useful feedback.

8. Latent error

Latent errors tend to represent those ‘hidden’ mistakes that happen only when a specific compilation of data is utilized. In most cases, this happens when a programmer doesn’t remember to deal with particular edge cases.

Unfortunately, latent errors can only be located when all possible combinations of the available data are utilized.

How to locate and solve possible errors

Apart from the instances described above, you might need some additional help with testing your algorithms and attempting to locate any possible errors. To that end, here are some methods that might help:

  • Using a debugger – A very helpful tool that is already integrated into most modern IDEs, a debugger will allow you to stop the code at any specific breakpoint, execute code by line, modify variables, examine the state of the software at runtime, and perform many other useful actions that will allow you to locate errors.
  • Dry running or desk checking – One of the most basic processes for finding errors within algorithms, dry running is done by executing each step of the algorithm one at a time while keeping a track of the results.
  • Using a trace table – Allowing you to check your code in as much detail as necessary, trace tables can also be particularly useful tools. To utilize them efficiently, keep in mind that the table rows show the state of one step in the code, while the columns show the values of the variables at those specific steps.
  • Rewriting the code – If you can’t seem to locate the error, but the code isn’t particularly long and you have enough time on your hands, you might want to attempt rewriting the code altogether. Although this is not a common practice (with some programmers even saying it should never be done), it might be a good solution for novices who are still practicing and developing their skills.
  • Asking for help – Sometimes the solution to your issues can be as simple as asking your colleagues or online communities for help, as chances are someone else has already come across and solved the specific issue you are facing. Even writing down your issues while asking for help might allow you to realize where the problem lies.

Final thoughts

Programing can often be a difficult job, the necessary demands tend to be unclear, and the algorithm has a habit of changing often. So, try not to be too hard on yourself, and remember that mistakes are an inevitable part of the procedure. Coding mistakes will undoubtedly continue to happen in the future, but the more you practice and learn, the more proficient you will be at noticing and correcting them on time.

This comprehensive guide will have hopefully explained the different forms of coding issues that you might encounter, as well as ways you could spot and correct them, thus preparing you for the unavoidable.