Учебное пособие состоит из двух частей и англо-русского словаря. Материалом для пособия послужило американское издание для изучающих компьютер P. Norton "Introduction to Computers"
Third-generation Programming Languages
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| Third-generation Programming Languages (Part II)
Unlike such third-generation languages as FORTRAN, COBOL, BASIC, Pascal, the following languages still have a thriving following and a bright future: C. Often regarded as the thoroughbred of programming languages, C produces programs with fast and efficient executable code. C is also a powerful language. With it, you can make a computer do just about anything it is possible for a computer to do. Because of this programming freedom, C is extremely popular with professional developers, although it is now being replaced by C++. C++. C++ is the object-oriented implementation of C. Like C, C++ is an extremely powerful and efficient language. Learning C++ means learning everything about C and then learning about object-oriented programming and its implementation with C++. Nevertheless, more C programmers move to C++ every year, and the newer language has replaced C as the language of choice among software development companies. Java. Java is an object-oriented programming environment for creating cross-platform programs. When the Internet became popular in the mid-1990s, Java's developer, Sun Microsystems, redeveloped Java to become a programming environment for the Web. With Java, Web designers can create interactive and dynamic programs (called applets) for Web pages. Essentially, a Java program is a self-contained, semicompiled function that makes no reference to outside code or operating system functions. Thus, Java code is fully compatible with most any computer and operating system. To create Java code, a developer writes the applet and then compiles it into bytecode. To run the Java applet, a user accesses the bytecode, perhaps over the Internet. Then, using a Java virtual machine, the client PC converts the bytecode into machine code appropriate to that particular computer. ActiveX. Microsoft's answer to Java is ActiveX. ActiveX code creates self-contained functions similar to Java applets that may be accessed and executed by any other ActiveX-compatible program on any ActiveX system or network. At present, ActiveX is implemented on Windows 9x, Windows NT, and Macintosh systems, and there are plans for supporting UNIX also. Of the third-generation languages, Java is probably the most important for the future development of PCs and the Internet. In fact, some developers see Java as a way of redefining the PC itself. By replacing the current expensive and platform-defining CPU with a cheap Java-decoding microchip, developers can create a machine that gets all of its software from Java servers on the Internet. To use such a machine, you would load a Web browser (also written in Java), connect to the Internet, and access Java programs for all of your software needs. If this prediction comes true, then all PCs will be both inexpensive and fully compatible. жүктеу/скачать 0,7 Mb. Достарыңызбен бөлісу:
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