Any program or online services, for example, Word, Microsoft Windows, WhatsApp, or a browser that hundreds of millions of people launch daily, one way or another, consists of special instructions. Or a special program code that the machine understands says what it should do or, conversely, not do. Or how to properly respond to user actions. What is the program code will be discussed in this article.
Description
The program code of the program is a text executed in a special language understood by the machine. It can be executed directly in the text using the interpreter or translated into a special form using the compiler.
The source code of the program may consist of several files. Moreover, they should all be of the same format. The text of the program contained in them must be written in the same language. True, there may be exceptions. For example, in web development, a page file may contain several different programming languages and standards. Depending on the complexity of the project, languages and technologies such as PHP, HTML, JavaScript, Java and others may be present.
Complex software systems during assembly may require a large number of files, which can be as many as hundreds. To work together on such large projects, programmers very often use version control systems. They allow you to simultaneously work with multiple instances of the source code, which at a certain stage of development can be combined into one common.
Code quality
The computer is not able to understand how the code is written for it, bad or good. If it is operational and does not contain errors, then the machine will start it in any case. Bad code can complicate software maintenance tasks. This is especially true for large projects. Typically, a quality code is characterized by several parameters:
- Code readability. One glance at it should be enough to generally understand what is implemented by a piece of code.
- The presence of clear and concise comments. This parameter greatly affects readability, ease of debugging, testing support and troubleshooting code.
- Low complexity.
- Code optimization. Organize it in such a way that the program uses as little system resources as possible, such as memory, processor time and hard disk space.
- Lack of garbage. That is, unused variables or blocks of code in which program control never enters.
Malicious code
In addition to useful programs, there are those that can harm the system or even the hardware. As a rule, such code is written by people who are interested in any benefit from the ongoing process. For example, programs that can steal personal data from users' computers. They can be payment card numbers, passport details, or some other confidential information. Others can simply influence the system, thereby causing crashes and interfering with full functionality.
Good Code Writing Guidelines
Jeff Vogel, a highly experienced programmer, shared some tips to teach novice developers the rules of good code.
In particular, he offers to always comment on his program code. What is a comment? This is a clear and concise description of what happens in a given line of code or function. The fact is that the development of a certain program can drag on for a month or even stop for a while. Returning to work on the project in a couple of months, even an experienced programmer will find it difficult to figure out his own program. But detailed comments can restore the chain of events and code behavior.
He further recommends using global variables in the program as often as possible. This is because when you change the program code, you have to adjust the value of the variable in only one place. At the same time, all functions or procedures that use the value will immediately know about it and will perform operations already with the new data.
Variable Names and Error Detection
The correct name of the variables will also help significantly reduce the time it takes to study the source code of the program, even if the code is written with your own hands. That is, good text is considered to be such text where variables and functions have names by which it is possible to understand what exactly they do or store. In this case, you should try not to use long variable names.
It is very important to pay great attention to timely troubleshooting. What is code that executes perfectly? This is code in which there are no errors. That is, any branching of a cycle or change of a variable, or any unexpected actions of a user at all, will always lead to the expected result. This is achieved by testing the finished software product several times.
Identification of program code errors, or rather, their prediction is possible at the program design stage. The presence in the code of various checks of conditions and possible exceptions will help to manage the program at a certain rate.
Optimization is of paramount importance for writing a workable program that will use the resources of a computer economically and at the same time avoid making program code errors. What is an optimized program? This is a product that is able to perform all the declared functionality, while behaving "quietly" and economically.
Almost always, optimization for stable operation of the program can be achieved only as a result of several tests on different platforms and in different conditions. If the program starts to behave unpredictably, you need to determine what caused it and, if possible, eliminate or intercept the process.
Conclusion
What is program code? In simple terms, this is a set of instructions and concepts for the computer. It contains text that the compiler or interpreter can turn into a machine-friendly language. That is, in fact, the program code is an intermediary between a person and a computer, which simplifies their relationship.