A programming language is a formal language comprising a set of instructions that produce various kinds of output. Programming languages are used in computer programming to implement algorithms. Most programming languages consist of instructions for computers.
Computer programming language is, any of various languages for expressing a set of detailed instructions for a digital computer. Such instructions can be executed directly when they are in the computer manufacturer-specific numerical form known as machine language, after a simple substitution process when expressed in a corresponding assembly language, or after translation from some “higher-level” language. Although there are many computer languages, relatively few are widely used.
Machine and assembly languages
A machine language consists of the numeric codes for the operations that a particular computer can execute directly. The codes are strings of 0s and 1s, or binary digits (“bits”), which are frequently converted both from and to hexadecimal (base 16) for human viewing and modification. Machine language instructions typically use some bits to represent operations, such as addition, and some to represent operands, or perhaps the location of the next instruction. Machine language is difficult to read and write, since it does not resemble conventional mathematical notation or human language, and its codes vary from computer to computer.
Assembly language is one level above machine language. It uses short mnemonic codes for instructions and allows the programmer to introduce names for blocks of memory that hold data. One might thus write “add pay, total” instead of “0110101100101000” for an instruction that adds two numbers.Get a Britannica Premium subscription and gain access to exclusive content.Subscribe Now
Assembly language is designed to be easily translated into machine language. Although blocks of data may be referred to by name instead of by their machine addresses, assembly language does not provide more sophisticated means of organizing complex information. Like machine language, assembly language requires detailed knowledge of internal computer architecture. It is useful when such details are important, as in programming a computer to interact with peripheral devices (printers, scanners, storage devices, and so forth).
Algorithmic languages are designed to express mathematical or symbolic computations. They can express algebraic operations in notation similar to mathematics and allow the use of subprograms that package commonly used operations for reuse. They were the first high-level languages.
The first important algorithmic language was FORTRAN (formula translation), designed in 1957 by an IBM team led by John Backus. It was intended for scientific computations with real numbers and collections of them organized as one- or multidimensional arrays. Its control structures included conditional IF statements, repetitive loops (so-called DO loops), and a GOTO statement that allowed nonsequential execution of program code. FORTRAN made it convenient to have subprograms for common mathematical operations, and built libraries of them.
FORTRAN was also designed to translate into efficient machine language. It was immediately successful and continues to evolve.
ALGOL (algorithmic language) was designed by a committee of American and European computer scientists during 1958–60 for publishing algorithms, as well as for doing computations. Like LISP (described in the next section), ALGOL had recursive subprograms—procedures that could invoke themselves to solve a problem by reducing it to a smaller problem of the same kind. ALGOL introduced block structure, in which a program is composed of blocks that might contain both data and instructions and have the same structure as an entire program. Block structure became a powerful tool for building large programs out of small components.
ALGOL contributed a notation for describing the structure of a programming language, Backus–Naur Form, which in some variation became the standard tool for stating the syntax (grammar) of programming languages. ALGOL was widely used in Europe, and for many years it remained the language in which computer algorithms were published. Many important languages, such as Pascal and Ada (both described later), are its descendants.
The C programming language was developed in 1972 by Dennis Ritchie and Brian Kernighan at the AT&T Corporation for programming computer operating systems. Its capacity to structure data and programs through the composition of smaller units is comparable to that of ALGOL. It uses a compact notation and provides the programmer with the ability to operate with the addresses of data as well as with their values. This ability is important in systems programming, and C shares with assembly language the power to exploit all the features of a computer’s internal architecture. C, along with its descendant C++, remains one of the most common languages.
COBOL (common business oriented language) has been heavily used by businesses since its inception in 1959. A committee of computer manufacturers and users and U.S. government organizations established CODASYL (Committee on Data Systems and Languages) to develop and oversee the language standard in order to ensure its portability across diverse systems.
COBOL uses an English-like notation—novel when introduced. Business computations organize and manipulate large quantities of data, and COBOL introduced the record data structure for such tasks. A record clusters heterogeneous data—such as a name, an ID number, an age, and an address—into a single unit. This contrasts with scientific languages, in which homogeneous arrays of numbers are common. Records are an important example of “chunking” data into a single object, and they appear in nearly all modern languages.
SQL (structured query language) is a language for specifying the organization of databases (collections of records). Databases organized with SQL are called relational, because SQL provides the ability to query a database for information that falls in a given relation. For example, a query might be “find all records with both last name Smith and city New York.” Commercial database programs commonly use an SQL-like language for their queries.
Java is a programming language expressly designed for use in the distributed environment of the Internet. It was designed to have the “look and feel” of the C++ programming language, but it is simpler to use than C++ and enforces an object-oriented programming model. ‘
Java is a programming language, designed to be concurrent, class based and object oriented, as well as a computing platform first released by Sun Microsystems in 1995. An enormous amount of applications and websites will not work unless you have Java installed, and more are created every day. Denying yourself Java is akin to denying yourself access to a technological infrastructure. Java is advertised, and esteemed for its fast performance, security, and reliability.
From laptops to datacenters, game consoles to scientific supercomputers, cell phones to the Internet, Java is ubiquitous.
TYPES OF JAVA
What is Java and types of Java?
The types of the Java programming language are divided into two categories: primitive types and reference types. The primitive types (§4.2) are the boolean type and the numeric types. The numeric types are the integral types byte , short , int , long , and char , and the floating-point types float and double .
Following are the notable features of Java:
In Java, everything is an Object. Java can be easily extended since it is based on the Object model.
Unlike many other programming languages including C and C++, when Java is compiled, it is not compiled into platform specific machine, rather into platform-independent byte code. This byte code is distributed over the web and interpreted by the Virtual Machine (JVM) on whichever platform it is being run on.
Java is designed to be easy to learn. If you understand the basic concept of OOP Java, it would be easy to master.
With Java’s secure feature it enables to develop virus-free, tamper-free systems. Authentication techniques are based on public-key encryption.
Java compiler generates an architecture-neutral object file format, which makes the compiled code executable on many processors, with the presence of Java runtime system.
Being architecture-neutral and having no implementation dependent aspects of the specification makes Java portable. The compiler in Java is written in ANSI C with a clean portability boundary, which is a POSIX subset.
Java makes an effort to eliminate error-prone situations by emphasizing mainly on compile time error checking and runtime checking.
With Java’s multithreaded feature it is possible to write programs that can perform many tasks simultaneously. This design feature allows the developers to construct interactive applications that can run smoothly.
Java byte code is translated on the fly to native machine instructions and is not stored anywhere. The development process is more rapid and analytical since the linking is an incremental and light-weight process.
With the use of Just-In-Time compilers, Java enables high performance.
Java is designed for the distributed environment of the internet.
Java is considered to be more dynamic than C or C++ since it is designed to adapt to an evolving environment. Java programs can carry an extensive amount of run-time information that can be used to verify and resolve accesses to objects at run-time.
IMPORTANCE OF JAVA
Java is one of the most popular programming languages used to create Web applications and platforms. It was designed for flexibility, allowing developers to write code that would run on any machine, regardless of architecture or platform. According to the Java home page, more than 1 billion computers and 3 billion mobile phones worldwide run Java.
Java is used to build applications and platforms for a number of devices, including computers, laptops, gaming consoles, Blu-ray players, car navigation systems, medical monitoring devices, parking meters, lottery terminals and smartphones. It is also a key language for networking, particularly for data centers that store and transfer Web-based data.
Java is also used to create miniature, dynamic programs that run alongside or are embedded within Web pages. These programs are called applets and can be used to display maps, weather, games or other interactive widgets or tools on a Web page.https://cc2509cefdc61a3a4d03daa4337ea410.safeframe.googlesyndication.com/safeframe/1-0-37/html/container.html
Based on a C and C++-based syntax, Java is object-oriented and class-based. Developers adopt and use Java because code can be run securely on nearly any other platform, regardless of the operating system or architecture of the device, as long as the device has a Java Runtime Environment (JRE) installed. The JRE varies depending on the specific type of device, but essentially it runs a “virtual” machine, or environment, that translates the code into an application or program.