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Learn javag or SQL
java is easier to use

I studied SAL programming myself, but it's useless.

I'm also studying C++ and JAVA

SQL, which is easier to understand.

It's more interesting to master Java.

I suggest you learn C++

which languages are needed for programming.

What is programming?

Simply put.

although computers are very powerful. It can be used for you to surf the Internet, play games, manage the company's personnel relations, etc., but without the program, it is equivalent to a pile of scrap iron and will not pay attention to the "orders" we give it. Therefore, we have to tame it in only one way-program, which is also the only way for us to communicate with computers.

what exactly is the program?

A program is a collection of instructions that tell a computer how to perform a special task.

For example, it is like instructing you to cook a menu or directing a traffic policeman (or a traffic sign) to drive all the way to your destination. Without these special instructions, the expected tasks cannot be carried out. The computer is the same. When you want the computer to do something for you, the computer itself can't actively work for us, so we must give instructions to it, and it can't and can't understand the description of things in human natural language at all, so we must use programs to tell the computer what to do and how to do it. Even the simplest tasks require instructions, such as how to get keystrokes, how to put a letter on the screen, how to save files on disk, and so on.

it's so troublesome, even the programming of these things should be considered! No wonder people say that programming is so difficult! You are wrong. In fact, many of these instructions are ready-made, contained in the processing chip and embedded in the operating system, so we don't have to worry about their work. They are all completed by the processor and the operating system, and we don't need to intervene in these processes.

The computer mentioned above will not do anything on its own initiative. Therefore, we should make the computer "serve" for us by means of programs. And this process is made up by us. Programming can be realized by using a certain programming language, and what the computer is asked to do is described according to the grammar of this language.

The grammar we are talking about here is completely different from the grammar in a foreign language. The grammar we are talking about here is just to read your program and write rules.

After writing the program, your program will be interpreted or translated into a "computer language" that the computer can recognize, and then the computer can "understand" your words and do things according to your instructions. Therefore, programming is actually a process of "people make rules for computers".

With the variety of computer languages, it can be generally divided into three categories: machine language, assembly language and high-level language.

Every action and step that a computer does is executed according to a program that has been programmed in computer language. A program is a collection of instructions that a computer needs to execute, and all the programs are written in the language we have mastered. Therefore, if people want to control the computer, they must send commands to the computer through computer language.

The only language that a computer can recognize is machine language, that is, the code composed of. But usually people don't use machine language when programming, because it is very difficult to remember and recognize.

At present, there are two general programming languages: assembly language and high-level language.

The essence of assembly language is the same as that of machine language, and both of them operate directly on hardware, except that the instructions use English abbreviated identifiers, which are easier to identify and remember. It also requires the programmer to write out each specific operation in the form of commands.

Each instruction of an assembler can only correspond to a very subtle action in the actual operation process, such as moving and adding itself. Therefore, the assembler source program is generally lengthy, complicated and error-prone, and more computer expertise is needed for programming in the assembler language. However, the advantages of the assembler language are also obvious. The operations that can be accomplished in the assembler language are not realized by ordinary high-level languages, and the executable files generated by the assembler source program are not only relatively small, but also very fast.

High-level language is the choice of most programmers at present. Compared with assembly language, it not only synthesizes many related machine instructions into a single instruction, but also removes details related to specific operations but not related to the completion of work, such as using stacks and registers, which greatly simplifies the instructions in the program. Because many details are omitted, programmers don't need to have too much professional knowledge.

High-level language is mainly relative to assembly language. It does not refer to a specific language, but includes many programming languages, such as VB, VC, FoxPro, Delphi, etc. These languages have different grammars and command formats.

(1) Interpretation class: The execution mode is similar to "simultaneous translation" in our daily life. The source code of the application is translated into the target code (machine language) and executed at the same time, so the efficiency is relatively low, and the executable file that can be executed independently cannot be generated. The application cannot be separated from its interpreter, but this method is flexible and can dynamically adjust and modify the application.

(2) compilation class: compilation refers to "translating" the program source code into the target code (machine language) before the application source code is executed, so the target program can be executed independently from its language environment, which is more convenient and efficient to use. However, once an application needs to be modified, it must first modify the source code, and then recompile to generate a new target file (*. obj) before it can be executed. It is inconvenient to modify only the target file without the source code. At present, most programming languages are compiled, such as Visual Basic, Visual C++, Visual Foxpro, Delphi and so on.

this question is actually very simple. As we said earlier, programs are the only way for people to communicate with computers, so if we want computers to serve us, we must have programs, and where do programs come from? Of course, it was written by us. Maybe you will ask another question: Why should I program when there are all the programs I want now? That's where you are wrong. Although there are many programs now, it won't take a long time to find a similar program directly on the Internet, and it may be just what you need. However, it's like buying clothes. Although clothes are sold everywhere, which one is "tailored" for you!

programs can also do many things. Different programs can do different things. From the big aspect to the management of national finance, the small aspect manages family accounts.

For another example, if you want your computer to play animation, you should also have a corresponding animation player in your computer. The following is an F1ssh animation player. We will describe the programming process of this program in detail in the later chapters.

With the rapid development of computers, people who can't program will be classified as "illiterate" one day. You don't want it, do you? Then learn a programming language well.

will programming become obsolete?

will programming become obsolete? Let me ask you a question first: Will computers disappear? The answer is the same. Knowing whether the computer will disappear, you will know whether programming will be out of date.

programming tools will be out of date, but programming will not be out of date

A computer system consists of a visible hard inverted system and an invisible software system. In order to make the computer work normally, it is impossible to have only a hardware system. A computer without a soft-down system (that is, without a program) can be said to be just a pile of scrap iron, and nothing can be done. For example, when you write an article, you need to use text editing software in the operating system to input the text, but without these text input software, have you ever thought about how to input the article into the computer? It's hard to imagine how to input words on a computer without any software (we call it bare metal). And these softwares are actually what we usually call programs.

will programming become obsolete? Let's consider this problem from another angle. Will computers ever disappear? If one day when computers are not used for everything in the world, computers will soon disappear, and then programming will not only be out of date, but also disappear with it. But will computers disappear? Of course not. Nowadays, computers are applied to every field, and have made immeasurable contributions to human development. Imagine what the world will look like if computers all over the world suddenly disappear one day. Maybe it will be as terrible as the power failure all over the world, and there will be even greater losses. The existence of a computer must be maintained by a software system. Therefore, programming will never and cannot become obsolete.

Today, the computer programming language has developed from the most primitive machine language to today's visual integrated development environment, and even set multiple languages on the same development platform, like Microsoft's NET platform. Looking back at the development history of programming languages, it is not difficult to see that for programming, only programming tools will be outdated, and programming itself will not be outdated.

Changing technology requires changing programmers

Since the 196s, computers have developed by leaps and bounds. It seems that no science in history has developed faster than computers, and hardware, software and networks have all developed at an alarming rate. The development speed of computer hardware follows Moore's Law and doubles every 18 months (actually it has exceeded this speed now). The development speed of software is the same as that of hardware. In the 199s, the software industry in China was not very mature. Now, large and small software enterprises stand everywhere, and * * * software can be found everywhere on the Internet. The ever-changing technology needs ever-changing programmers. For example, nowadays Visual Basic can quickly build applications under Windows, and the technology of programming is constantly developing, and new concepts and methods are constantly introduced. For example, starting with structured C, when the object-oriented idea was put forward, C++ appeared. On the basis of C++, Microsoft introduced Visual C++ to make it easier for users to build win32 applications. This also requires programmers to constantly update their own technology.

Computer science is very different from other disciplines. Unlike linguistics and history, it is almost permanent. Computer science requires constantly updating its knowledge, otherwise it will soon be eliminated, even in programming.

programming is a very interesting thing, because it can do many advanced things. For example, in the following chapters, we introduce how to use Visual Basic to write a Flash animation player and how to write a download software manager. You can write more advanced programs than these if you like.

With the development of computer software industry, the position of "programmer" was born. Therefore, an idea is formed that the person who writes the program sequence is the programmer, so programming is the programmer's business. But programmers are not programmers from the beginning, and they have gradually become programmers from our present position.

programming is a very interesting thing, because it can do many advanced things. For example, in the following chapters, we introduce how to use Visual Basic to write a Flash animation player and how to write a download software manager. You can write more advanced programs than these if you like.

Programming can also be used as a hobby or interest. If you are interested in it, it will be much easier to learn! Because if you are interested in programming, you will read more books about it and compile more small programs to practice on the computer, which is very helpful for learning programming, and with the continuous advancement of the learning process, you will find it is not very difficult, but on the contrary, it is very easy.

In short, we must persevere in learning programming, and we will learn it well as long as we have confidence and perseverance. You can't shake your confidence because of some specious ideas.

Let's program

how to operate the computer in front of us. I believe this problem is no longer the primary problem that puzzles everyone. Now there are so many kinds of software, when choosing it, did the "computer enthusiast" ever think that one day he could write his own software? Will friends who want to learn programming have a big headache when choosing a programming language because they don't know how to choose it? When I don't know how to start, will friends have the idea of "can I program?" But which programmer can succeed without learning! In fact, programming is not as difficult and complicated as people think, and every friend who is committed to learning computers can try!

the necessity of choosing a suitable programming language

At present, there are many kinds of basic programming languages in common use, such as Pascal, C language, qBasic, Fortran, Visual Basic and so on. But the first few are all programming tools under DOS, and Visual Basic is a programming tool for application design under Windows. Now most computer users no longer use DOS, so we usually choose Visual Basic as a programming tool for beginners. Visual Basic is the easiest programming tool to use in Windows application design, and the learning steps are easily accepted by beginners. For beginners who have just started to learn programming, Visual Basic is still chosen. Learning programming languages cannot be imagined as the best way, and learning step by step is the best way.

strengthen your confidence in learning to write programs

Writing programs is not a patent for people with professional knowledge. Everyone who studies computers can write programs. Everyone has different inspirations and different ideas and practices in writing programs. But the same idea is to write a successful program. Learning programming is a long process, which requires hard work and sweat, but the joy of a successful person is beyond others' understanding. Overcome the difficulties in learning, work hard to practice, and have an idea: what others can do can be done by themselves. The popularity of computers gives more people the opportunity to learn, and also allows more people to participate in the ranks of programmers. Everyone has the right to program, and opportunities are equal to everyone. Take out your confidence to win, be brave in making progress on the road of programming, and believe that success will be in sight.

Third, can I program?

With the development of computer software industry, the position of "programmer" was born. So an idea was formed,