Computer Programming

Flowchart

A flowchart is a graphical representation of a sequence of events, process, or an organizational structure. A flowchart is used to provide a reference point when dealing with a process. Common flowchart elements include a diamond, which represents a decision point; a square, which represents a process; a rhombus or parallelogram, which represents an input or output point; an oval, which represents the beginning or end of a process; and an arrow, which describes the direction of flow for the chart.

Programming Language

A programming language is a type of language or "code" for the set of instructions and commands the CPU must perform. Programming language uses a collection of symbols, letters and words that instruct the computer to perform specific operations.

The six steps of the SDLC are:

Investigation Analysis Design Development Implementation Maintenance

JSON

JavaScript Object Notation (JSON) is an open-standard format that uses human readable text to transmit data objects. JSON supports asynchronous browser/server communication. The use of natural language statements makes easy for humans to interact, resulting in it quickly replacing XML.

SDLC - Maintaining the System

Maintaining the system includes 2 phases: systems audit and routine evaluation. A systems audit is when system performance is compared to the original system design specification The evaluation phase is when the new system is continually monitored to ensure that is running optimally.

PDLC - Developing the code

Once the plan or algorithm has been created, it is then translated into programming code, a language that is friendlier to humans than the computer language that the CPU uses, but is still highly structured. While coding the algorithm programmers must think in terms of the operations that a CPU can perform.

Pseudocode

Pseudocode is a detailed, readable explanation of what a computer program or algorithm must do. Pseudocode is like an outline. Pseudocode uses different levels that show the flow of actions within a program. There is no standard language, instead it is a combination of words and special words that act as commands in the programming language.

Why study programming?

Top programmers, or coders, are among the most highly paid and sought-after employees in the US job market. Even a small degree of programming knowledge can be valuable. Off-the-shelf software programs include many of the features you will need, however, having a basic knowledge of programming allows you to create software that better meets your personal needs. Most software applications let you customize using mini programs called macros. Creating macros allows you to execute complex actions using a single command. You can create macros in Microsoft Word and Excel. An understanding of programming will also allow you to create new applications which is big business.

Top-down programming design

Top-down program design is an organized approach that breaks down a problem into a series of tasks. Using this approach programmers break each task into detailed subtasks. The process continues until the sequence of steps is closely aligned to types of commands permitted by the programming language that is used for coding.

Objective C, Swift, and Cocoa

When Apple bought NeXT in 1997, Objective C became the programming language used on all Macintosh computers and later, on iPhones. Because Objective C uses the syntax and symbols of C, it had a reputation for being hard to learn and use. Swift is a programming language introduced by Apple that allows programmers to develop software for iOS and OS X that is simpler to learn and use than Objective C. Swift is often used with Cocoa which is a programming environment for the OS X user interface. Cocoa Touch is used to code gesture recognition used in the iPhone and iPad.

Object-oriented analysis

When object-oriented analysis is used, programmers first identify all of the categories of inputs that are needed to solve the problem. The input categories are called classes and objects are examples of the input item used in each class. Programmers using object-oriented analysis spend a lot of time identifying classes and establishing the relationships between each class. In order to get the algorithm to work, programmers may need to create different objects to serve as examples of a class. One benefit of this approach is the ability to reuse objects to produce new computer code. This is referred to as reusability.

XML

eXtensible Markup Language (XML) makes it easier to have documents on the Web. It provides for relatively straightforward translation between documents that users can read and machine language. Hundreds of programming formats use XML to create documents for use on the Web. XML wraps data into tags that can be displayed on the Web. XML doesn't use predefined tags. Tags are created by the XML document author. XML was designed to simplify data changes, sharing, transport, and availability. Before using XML it is a good idea to have a working knowledge of HTML and JavaScript.

Compiler

A compiler is a program that acts as an intermediary between the syntax of the programming language and the structure of the CPU and its machine language. The compiler can read the source code which includes programming instructions written in high-level computer language and translates the source code into the specific machine language. Most programming languages have their own built-in compiler. If the programming language doesn't have a compiler it is likely that an interpreter is used. An interpreter translates source code line by line and then executes the command as it is translated. This makes the compilation process more tedious and time consuming.

JavaScript and VBscript

A script is a small program that completes a specific task. A scripting language is a high-level language that uses scripts to create larger programs. JavaScript was created to work with the various components of a web page. JavaScript uses the syntax and operators used in Java. JavaScript includes various classes that represent popular objects used on Web pages including buttons, check boxes, and drop-down lists. Another popular scripting language is VBScript. VBScript allows for dynamic decision making which allows the page to determine how it will be displayed based on the viewing behavior of the user.

Define a system

A system is a group of related elements that work together to achieve a common goal. Your car, for example is a system of computers, parts, and machines designed to work together to allow you to drive. An information system includes people, techniques, data, information, software, and hardware that work together to execute a common task or goal. Information systems are widely used by e-commerce and traditional companies such as your college, BestBuy, and the US Government.

PDLC - Creating the plan

After the problem has been specifically identified, a plan is created to design the program that will solve the problem. This plan is a set of specific, sequential steps that describe exactly what the computer program must do to complete the work. The steps are known as an algorithm. At this stage, the algorithm is written in natural, ordinary language (such as English).

Algorithm

An algorithm is a set of specific consecutive steps that describe exactly what steps the computer must go through to execute a task. Algorithms may sound only like a computing term but you actually use them whenever you make a decision. Computer programmers write algorithms using flowcharts and in a natural language, such as English, so that the algorithm can be seen and read by as many editors as necessary. Using a flowchart makes the algorithm easier to convert to a computer programming language such as Java.

Interpreter

An interpreter is a program that converts a small portion of code into machine language. When a programmer has compiled a program and needs to make a small change, they often use an interpreter to "test" a new line of code rather then compile the entire program. This allows programmers to see if these small changes will work when converted to machine language.

AJAX

Asynchronous JavaScript and XML (AJAX) is not a programming language or tool, but a set of programs. Ajax allows for the exchange of information and data with a server that automatically updates parts of a Web page without having to refresh. Ajax exchanges data without needing to change the data being displayed on the webpage. This provides for a more responsive user experience. Ajax uses the protocols of the Extensible Markup Language (XML) to exchange data.

Basic and Visual Basic

BASIC stands for Beginner's All Purpose Symbolic Instruction Code. It was an easy programming language to use and was popular when most computers were DOS-based. Now that computers use a graphical user interface, Visual Basic is more common. Visual Basic is used to build a wide variety of Windows applications as well as Web and mobile apps. Visual Basic provides the following advantages: ---Uses a consistent object-oriented programming environment across a wide variety of applications, including Windows applications and Web-based applications. ---Creates an environment that allows for the safe execution of code, including code created by a third party.

Binary Decisions

Binary decisions act similar to a "fork in the road". Binary decisions can be answered in two ways: yes (the statement is true) or no (the statement is false).

C and C++

C is the most popular programming language of all time. It provides the foundation for C++. Developed in the early 1970s, it provides a smooth translation to machine language. It is a structured programming language, which means it uses subroutines and loops to make programming easier. The Unix operating system was written in C, and most modern operating systems such as Microsoft Windows, and the Mac OS X were based on Unix. C++ is based on C. C++ is a high-level programming language that allows for object-oriented programming.

PDLC - Debugging the code

Despite the best efforts of programmers, there are nearly always problems with the initial coding. The process of removing these issues is called debugging. Debugging means removing any errors in the program. There are several methods that programmers use to debug code. Most involve a system of trial and error where the programmer attempts to isolate the problem area and then examine the lines of code to determine the error. This is commonly called the divide-and-conquer method.

SDLC - Designing the System

During the design step multiple proposals for developing the new system are proposed and analyzed. Each alternative is assessed based on its economic, technical and operational feasibility. The next phase consists of selecting the best system from among the alternatives. Important questions about the system should be addressed. Specific questions include: How will the system work with the existing information system? Can the system be modified to meet future demands? What are the security requirements of the new system? What are the costs vs. the benefits of the new system? The final phase in the design step is to create a systems design report stating the conclusions of the design step.

HTML and HTML 5

Hypertext Markup Language, called HTML, provides a way to display content on the Web. Content written to be displayed on the Web must include special symbols called tags. Tags control how web browsers display content including images, text, and other multimedia content tagged in HTML. Adobe Dreamweaver and Microsoft Visual Studio Express are popular programs that assist with the generation of HTML content. HTML5 is the fifth revision to HTML and allows the integration of JavaScript animation and other types of multimedia. HTML5 allows for increased compatibility with a variety of Web browsers.

SDLC - System Implementation

Implementation involves converting the old system to the new system. This involves extensive training on how to use the new system. There are two major phases of implementation: conversion and training. There are four widely used approaches to conversion: direct, parallel, pilot, and phased. Once a conversion strategy has been chosen it is important to train personnel on how the new system works and how to properly use the system. This is a critical step to ensure all stakeholders are properly and efficiently using the new system.

Loop

In a loop a question is asked. If the answer to the question is yes, a sequence of actions is executed. Once that sequence of actions is finished, the question is asked again, which creates a loop. As long as the answer to the question is yes, the loop will continue to repeat the same set of actions. Loops include three important features: ---Initial value ---Actions to be performed ---Test condition. A test condition is a check to see if the loop has been completed.

SDLC - System Investigation

Investigation includes three phases: defining the problem, proposing alternatives, and reporting. Defining the problem includes analyzing the current situation and information system in use. Common questions include: What information is needed? Who needs the information? When do they need it? How much will it cost? and Why do they need the information? The next phase is proposing alternatives. This means studying alternative solutions to the present arrangement or problem. This task includes the suggestion of possible plans that are different than the current situation. The final phase in the investigation step is creating the report. During this phase the system analyst prepares a report that is given to upper management that summarizes the results of the investigation and proposes alternative system solutions.

Describe the SDLC

It is important to have a prescribed process when developing software. This ensures that the software that is developed meets organizational goals, can work as intended on multiple operating systems, be free of errors, and have plenty of end-user support. When developing software the System Development Life Cycle (SDLC) is commonly used. The SDLC consists of six steps. You cannot proceed to the next step in the SDLC until the current step has been completed.

Java and C#

Java is a programming language that uses an object-oriented programming model, designed for use on graphical user interface (GUI) platforms. Java uses architecture neutrality which means that code needs to be compiled only once which allows it to be compatible with many different CPUs. Java is most commonly used to write apps for Android-based smartphones and tablets, as well as for writing web-based apps. C# began as C-like Object Oriented Language or COOL, but was changed to C# when Microsoft purchased it. C# and Java have similar qualities and advantages. C# is most commonly used to write programs for Windows desktops, servers and phones.

Program Development Lifecycle (PDLC)

Most programming projects use a prescribed set of stages to complete the project. This process is often referred to as the Program Development Life Cycle (PDLC). The PDLC consists of 5 steps: defining the problem, creating a plan, writing the code, debugging the code, and testing the code.

SDLC - Developing the System

The development stage of the system development life cycle includes purchasing the necessary hardware and software. Not all new systems will require new hardware. In the event it is determined that new hardware must be purchased it is important to assess what will be needed and how much it will cost. After new software and hardware has been installed it is critical to test the system components to ensure they are working properly. During this phase it is important to note any issues and revise the system as necessary.

PDLC - Testing the code

The final step in the program development life cycle is testing the software by both the programming team and the people who will use the program. The results of the entire project are documented for the users and the development team. Finally, users are trained so that they can use the program efficiently.

SDLC - System Analysis

The first phase involves gathering the data. During this phase the systems analyst collects data by a variety of means including surveys, interviews, reviews of standard operating procedures, and by examining organizational charts or other appropriate sources. Next, this data is analyzed to gain a better understanding of how information flows and what are the issues that impact the efficient flow of information. Finally, the analyst prepares a system specification report that describes the current information system, the requirements for a new system, schedules, and analysis of costs.

PDLC - Defining the problem

The initial step in the program development life cycle is determining what problem this new software will solve. Programmers must develop a complete description of the problem. The problem statement identifies the task to be automated and describes how the software program will perform. It takes into account the incoming data, the desired output, and how the output will be used.

Define programming

The method of converting a task into a sequence of commands that a digital device will use to perform a specific task. Programming involves categorizing which parts of a task a digital device can perform, describing the tasks in a precise manner, then translating into the language the computer's CPU can understand. One of the first steps of programming is the problem statement, which includes specifically what is trying to be accomplished. If the project is determined to be practical, programming to solve the problem will begin.