Definition:
In software development, a variable is a symbolic name that stores a value which can change (or “vary”) during the execution of a program. Variables act as containers for data—whether it’s a number, a string of text, a boolean (true/false), an object, or even a more complex structure like an array or function.

They are one of the most fundamental building blocks of programming and are used to temporarily hold data that is referenced and manipulated throughout the code.

Why Variables Matter:
Variables make software dynamic and functional. They allow developers to:

• Store user inputs

• Perform calculations

• Control logic and decision-making

• Reuse data efficiently

• Create readable, maintainable code

Without variables, code would be static and unable to react to different inputs or changing states.

Definition:
In software development, a dependency is any external code, library, module, or service that a software application relies on to function properly. Dependencies are typically third-party packages or components that provide reusable functionality—such as handling HTTP requests, formatting dates, managing authentication, or interacting with databases.

These are often installed and managed through package managers (like npm for JavaScript, pip for Python, or Composer for PHP) and are declared in a project’s configuration file.

Why Dependencies Matter:
Dependencies help developers move faster by reusing tested, maintained code instead of reinventing the wheel. They allow software teams to focus on business logic rather than low-level implementations of common features.

However, they also introduce risk and complexity, because:

• If a dependency breaks, your app might break.

• If a dependency becomes outdated or unmaintained, it can create security vulnerabilities or compatibility issues.

• Too many dependencies can increase the size of your codebase and make deployment slower or more fragile.

Types of Dependencies:

• Direct Dependencies: Packages your application explicitly includes and uses.

• Transitive (Indirect) Dependencies: Packages required by your dependencies—added automatically by the package manager.

• Development Dependencies: Tools or libraries used only during development (like testing frameworks or build tools).

• Runtime Dependencies: Libraries required for the application to run in production.

Example:
A JavaScript web app might use:

• Express.js as a direct dependency for routing

• Body-parser (used by Express) as a transitive dependency

• Jest as a development dependency for testing

Definition:
In software development, a token is a small piece of data that represents authentication, authorization, or other contextual information in a secure, compact format. Tokens are typically used to verify the identity of a user or system, grant access to resources, and maintain session state across distributed applications.

There are several types of tokens, with the most common being:

• Access Tokens – Used to authorize access to an API or resource.

• Refresh Tokens – Used to obtain new access tokens without re-authenticating the user.

• CSRF Tokens – Used to prevent cross-site request forgery attacks.

• JWT (JSON Web Tokens) – Self-contained tokens that include encoded information and can be verified without database lookups.

Common Use Cases:

• API Authentication: A client application sends a token with each request to authenticate and access a protected resource.

• Single Sign-On (SSO): Tokens allow users to log in once and access multiple systems without re-authenticating.

• Session Management: Tokens are used instead of cookies to manage user sessions in stateless applications, especially in mobile and modern web apps.

Definition:
Churn risk refers to the likelihood that a customer or user will stop using a software product or service. It’s often influenced by poor onboarding, lack of feature fit, performance issues, or lack of long-term value.

Why It Matters:
Understanding and reducing churn is critical for SaaS businesses and custom platforms alike. It ties directly to user experience, product-market fit, and customer success efforts.

Definition:
Change management is the structured approach to planning, implementing, and monitoring changes to software, systems, or business processes. It includes communication, training, testing, and feedback loops.

Why It Matters:
Even the best tools can fail if users aren’t prepared for change. Effective change management ensures adoption, minimizes disruption, and aligns technical changes with business needs.

Definition:
Data silos occur when information is stored in isolated systems or departments that don’t share data with others. This creates redundancy, inefficiency, and inconsistencies across the organization.

Why It Matters:
Breaking down data silos is essential for unified reporting, automation, and strategic decision-making. Integrations and central data platforms help eliminate these barriers.