|
Data Abstraction
In software engineering and computer science, abstraction is the process of generalizing concrete details, such as attributes, away from the study of objects and systems to focus attention on details of greater importance. Abstraction is a fundamental concept in computer science and software engineering, especially within the object-oriented programming paradigm. Examples of this include: * the usage of abstract data types to separate usage from working representations of data within programs; * the concept of functions or subroutines which represent a specific way of implementing control flow; * the process of reorganizing common behavior from groups of non-abstract classes into abstract classes using inheritance and sub-classes, as seen in object-oriented programming languages. Rationale Computing mostly operates independently of the concrete world. The hardware implements a model of computation that is interchangeable with others. The software is structured in archit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software Engineering
Software engineering is a branch of both computer science and engineering focused on designing, developing, testing, and maintaining Application software, software applications. It involves applying engineering design process, engineering principles and computer programming expertise to develop software systems that meet user needs. The terms ''programmer'' and ''coder'' overlap ''software engineer'', but they imply only the construction aspect of a typical software engineer workload. A software engineer applies a software development process, which involves defining, Implementation, implementing, Software testing, testing, Project management, managing, and Software maintenance, maintaining software systems, as well as developing the software development process itself. History Beginning in the 1960s, software engineering was recognized as a separate field of engineering. The development of software engineering was seen as a struggle. Problems included software that was over ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Model Of Computation
In computer science, and more specifically in computability theory and computational complexity theory, a model of computation is a model which describes how an output of a mathematical function is computed given an input. A model describes how units of computations, memories, and communications are organized. The computational complexity of an algorithm can be measured given a model of computation. Using a model allows studying the performance of algorithms independently of the variations that are specific to particular implementations and specific technology. Categories Models of computation can be classified into three categories: sequential models, functional models, and concurrent models. Sequential models Sequential models include: * Finite-state machines * Post machines ( Post–Turing machines and tag machines). * Pushdown automata * Register machines ** Random-access machines * Turing machines * Decision tree model * External memory model Functional models Functio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scripting Language
In computing, a script is a relatively short and simple set of instructions that typically automation, automate an otherwise manual process. The act of writing a script is called scripting. A scripting language or script language is a programming language that is used for scripting. Originally, scripting was limited to automating an operating system shell and languages were relatively simple. Today, scripting is more pervasive and some languages include modern features that allow them to be used for Application software, application development as well as scripting. Overview A scripting language can be a general purpose language or a domain-specific language for a particular environment. When embedded in an application, it may be called an extension language. A scripting language is sometimes referred to as very high-level programming language if it operates at a high level of abstraction, or as a control language, particularly for job control languages on mainframes. The te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-level Programming Language
A high-level programming language is a programming language with strong Abstraction (computer science), abstraction from the details of the computer. In contrast to low-level programming languages, it may use natural language ''elements'', be easier to use, or may automate (or even hide entirely) significant areas of computing systems (e.g. memory management), making the process of developing a program simpler and more understandable than when using a lower-level language. The amount of abstraction provided defines how "high-level" a programming language is. In the 1960s, a high-level programming language using a compiler was commonly called an ''autocode''. Examples of autocodes are COBOL and Fortran. The first high-level programming language designed for computers was Plankalkül, created by Konrad Zuse. However, it was not implemented in his time, and his original contributions were largely isolated from other developments due to World War II, aside from the language's influe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Third-generation Programming Language
A third-generation programming language (3GL) is a high-level programming language, high-level computer programming language that tends to be more machine-independent and programmer-friendly than the machine code of the First-generation programming language, first-generation and assembly languages of the Second-generation programming language, second-generation, while having a less specific focus to the Fourth-generation programming language, fourth and Fifth-generation programming language, fifth generations. Examples of common and historical third-generation programming languages are ALGOL, BASIC, C (programming language), C, COBOL, Fortran, Java (programming language), Java, and Pascal (programming language), Pascal. Characteristics 3GLs are much more machine-independent and more programmer-friendly. This includes features like improved support for aggregate data types, and expressing concepts in a way that favors the programmer, not the computer. A third generation language imp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Assembly Language
In computing, assembly language (alternatively assembler language or symbolic machine code), often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence between the instructions in the language and the architecture's machine code instructions. Assembly language usually has one statement per machine instruction (1:1), but constants, comments, assembler directives, symbolic labels of, e.g., memory locations, registers, and macros are generally also supported. The first assembly code in which a language is used to represent machine code instructions is found in Kathleen and Andrew Donald Booth's 1947 work, ''Coding for A.R.C.''. Assembly code is converted into executable machine code by a utility program referred to as an '' assembler''. The term "assembler" is generally attributed to Wilkes, Wheeler and Gill in their 1951 book '' The Preparation of Programs for an Electronic Dig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Second-generation Programming Language
The label of second-generation programming language (2GL) is a generational way to categorize assembly languages. They belong to the low-level programming languages. The term was coined to provide a distinction from higher level machine independent third-generation programming languages (3GLs) (such as COBOL, C, or JavaScript) and earlier first-generation programming languages (machine code) Second-generation programming language Second-generation programming languages have the following properties: *Lines within a program correspond directly to processor commands, essentially acting as a mnemonic device overlaying a first generation programming language. *The code can be read and written by a programmer. To run on a computer it must be converted into a machine readable form, a process called assembly. *The language is specific to a particular processor family and environment. Second-generation languages are sometimes used for parts of kernels or device drivers, and are some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Machine Language
In computer programming, machine code is computer code consisting of machine language instructions, which are used to control a computer's central processing unit (CPU). For conventional binary computers, machine code is the binaryOn nonbinary machines it is, e.g., a decimal representation. representation of a computer program that is actually read and interpreted by the computer. A program in machine code consists of a sequence of machine instructions (possibly interspersed with data). Each machine code instruction causes the CPU to perform a specific task. Examples of such tasks include: # Load a word from memory to a CPU register # Execute an arithmetic logic unit (ALU) operation on one or more registers or memory locations # Jump or skip to an instruction that is not the next one In general, each architecture family (e.g., x86, ARM) has its own instruction set architecture (ISA), and hence its own specific machine code language. There are exceptions, such as the V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
First-generation Programming Language
A first-generation programming language (1GL) is a machine-level programming language and belongs to the low-level programming languages. A first generation (programming) language (1GL) is a grouping of programming languages that are machine level languages used to program first-generation computers. Originally, no translator was used to compile or assemble the first-generation language. The first-generation programming instructions were entered through the front panel switches of the computer system. The instructions in 1GL are made of binary numbers, represented by 1s and 0s. This makes the language suitable for the understanding of the machine but far more difficult to interpret and learn by the human programmer. The main advantage of programming in 1GL is that the code can run very fast and very efficiently, precisely because the instructions are executed directly by the central processing unit (CPU). One of the main disadvantages of programming in a low level languag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programming Language
A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually defined by a formal language. Languages usually provide features such as a type system, Variable (computer science), variables, and mechanisms for Exception handling (programming), error handling. An Programming language implementation, implementation of a programming language is required in order to Execution (computing), execute programs, namely an Interpreter (computing), interpreter or a compiler. An interpreter directly executes the source code, while a compiler produces an executable program. Computer architecture has strongly influenced the design of programming languages, with the most common type (imperative languages—which implement operations in a specified order) developed to perform well on the popular von Neumann architecture. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Language
A computer language is a formal language used to communicate with a computer. Types of computer languages include: * Software construction#Construction languages, Construction language – all forms of communication by which a human can Computer programming, specify an executable problem solution to a computer ** Command language – a language used to control the tasks of the computer itself, such as starting programs ** Configuration file#Configuration languages, Configuration language – a language used to write configuration files ** Programming language – a formal language designed to communicate instructions to a machine, particularly a computer ***Scripting language – a type of programming language which typically is interpreted at runtime rather than being compiled ** Query language – a language used to make Information retrieval, queries in databases and information systems ** Transformation language – designed to transform some input te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modeling Languages
A modeling language is any artificial language that can be used to express data, information or knowledge or systems in a structure that is defined by a consistent set of rules. The rules are used for interpretation of the meaning of components in the structure of a programming language. Overview A modeling language can be graphical or textual. * ''Graphical'' modeling languages use a diagram technique with named symbols that represent concepts and lines that connect the symbols and represent relationships and various other graphical notation to represent constraints. * ''Textual'' modeling languages may use standardized keywords accompanied by parameters or natural language terms and phrases to make computer-interpretable expressions. An example of a graphical modeling language and a corresponding textual modeling language is EXPRESS. Not all modeling languages are executable, and for those that are, the use of them doesn't necessarily mean that programmers are no longer requ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
