Software testing in the context of Club Penguin

Computer programming or coding is the composition of sequences of instructions, called programs, that computers can follow to perform tasks. It involves designing and implementing algorithms, step-by-step specifications of procedures, by writing code in one or more programming languages. Programmers typically use high-level programming languages that are more easily intelligible to humans than machine code, which is directly executed by the central processing unit. Proficient programming usually requires expertise in several different subjects, including knowledge of the application domain, details of programming languages and generic code libraries, specialized algorithms, and formal logic.

Auxiliary tasks accompanying and related to programming include analyzing requirements, testing, debugging (investigating and fixing problems), implementation of build systems, and management of derived artifacts, such as programs' machine code. While these are sometimes considered programming, often the term software development is used for this larger overall process – with the terms programming, implementation, and coding reserved for the writing and editing of code per se. Sometimes software development is known as software engineering, especially when it employs formal methods or follows an engineering design process.

A debugger is a computer program used to test and debug other programs (the "target" programs). Common features of debuggers include the ability to run or halt the target program using breakpoints, step through code line by line, and display or modify the contents of memory, CPU registers, and stack frames.

The code to be examined might alternatively be running on an instruction set simulator (ISS), a technique that allows great power in its ability to halt when specific conditions are encountered, but which will typically be somewhat slower than executing the code directly on the appropriate (or the same) processor. Some debuggers offer two modes of operation, full or partial simulation, to limit this impact.

Software development is the process of designing, creating, testing, and maintaining software applications to meet specific user needs or business objectives. The process is more encompassing than programming, writing code, in that it includes conceiving the goal, evaluating feasibility, analyzing requirements, design, testing and release. The process is part of software engineering which also includes organizational management, project management, configuration management and other aspects.

Software development involves many skills and job specializations including programming, testing, documentation, graphic design, user support, marketing, and fundraising.

White-box testing (also known as clear box testing, glass box testing, transparent box testing, and structural testing) is a method of software testing that tests internal structures or workings of an application, as opposed to its functionality (i.e. black-box testing). In white-box testing, an internal perspective of the system is used to design test cases. The tester chooses inputs to exercise paths through the code and determine the expected outputs. This is analogous to testing nodes in a circuit, e.g. in-circuit testing (ICT).White-box testing can be applied at the unit, integration and system levels of the software testing process. Although traditional testers tended to think of white-box testing as being done at the unit level, it is used for integration and system testing more frequently today. It can test paths within a unit, paths between units during integration, and between subsystems during a system–level test. Though this method of test design can uncover many errors or problems, it has the potential to miss unimplemented parts of the specification or missing requirements. Where white-box testing is design-driven, that is, driven exclusively by agreed specifications of how each component of software is required to behave (as in DO-178C and ISO 26262 processes), white-box test techniques can accomplish assessment for unimplemented or missing requirements.

White-box test design techniques include the following code coverage criteria:

In software project management, software testing, and software engineering, verification and validation is the process of checking that a software system meets specifications and requirements so that it fulfills its intended purpose. It may also be referred to as software quality control. It is normally the responsibility of software testers as part of the software development lifecycle. In simple terms, software verification is: "Assuming we should build X, does our software achieve its goals without any bugs or gaps?" On the other hand, software validation is: "Was X what we should have built? Does X meet the high-level requirements?"

Black-box testing, sometimes referred to as specification-based testing, is a method of software testing that examines the functionality of an application without peering into its internal structures or workings. This method of test can be applied virtually to every level of software testing: unit, integration, system and acceptance. Black-box testing is also used as a method in penetration testing, where an ethical hacker simulates an external hacking or cyber warfare attack with no knowledge of the system being attacked.

Google AdSense is a program run by Google through which website publishers in the Google Network of content sites serve text, images, video, or interactive media advertisements that are targeted to the site content and audience. These advertisements are administered, sorted, and maintained by Google. They can generate revenue on either a per-click or per-impression basis. Google beta-tested a cost-per-action service, but discontinued it in October 2008 in favor of a DoubleClick offering (also owned by Google). In Q1 2014, Google earned US$3.4 billion ($13.6 billion annualized), or 22% of total revenue, through Google AdSense. In 2021, more than 38 million websites used AdSense. It is a participant in the AdChoices program, so AdSense ads typically include the triangle-shaped AdChoices icon. This program also operates on HTTP cookies.

Mutation testing (or mutation analysis or program mutation) is used to design new software tests and evaluate the quality of existing software tests. Mutation testing involves making small changes to the program being tested. Each changed version is called a mutant. A test detects, and rejects, a mutant when the test fails because the test is able to tell that the behaviour of the mutant differs from that of the original code. Rejection is called killing the mutant. The value of a test suite is measured by the percentage of mutants that it kills. The test suite can then be improved by adding new tests designed to kill additional mutants.

Mutant creation is done using well-defined mutation operators that either mimic typical programming errors (such as using the wrong operator or variable name) or force the creation of valuable tests (such as dividing each expression by zero).

The waterfall model is the process of performing the typical software development life cycle (SDLC) phases in sequential order. Each phase is completed before the next is started, and the result of each phase drives subsequent phases. Compared to alternative SDLC methodologies such as Agile, it is among the least iterative and flexible, as progress flows largely in one direction (like a waterfall) through the phases of conception, requirements analysis, design, construction, testing, deployment, and maintenance.The waterfall model is the earliest SDLC methodology.When first adopted, there were no recognized alternatives for knowledge-based creative work.

A debugger is software for executing a computer program in an environment that allows for programming-level inspection and control. A debugger is often used to debug, but can be used for other goals including testing. Common features of a debugger include stepping through code line-by-line, breaking into the program's flow of control, managing breakpoints, and reporting and modifying memory.

A source-level debugger (a.k.a. symbolic debugger) provides a user experience that integrates the program's source code. Typically, such a debugger can indicate which line of source code corresponds to the execution point of the program and allows for reading and writing memory via the symbols of the source code. In contrast, a low-level debugger (a.k.a. machine-language debugger) shows the execution point as machine code or its associated assembly language and allows memory access by address only.