Software applications are programs you run on your device to do a specific task
A software application (or app) is a program designed to perform one or more tasks on your computer, phone, or tablet. Unlike the operating system — which manages your device itself — an application does the actual work you want done: write a document, edit a photo, send an email, play music, or track your budget. Applications sit on top of the operating system and use it to access your device's hardware, like the screen, keyboard, and storage.
Most applications you use fall into a few broad categories. Productivity software includes word processors, spreadsheets, and note-taking tools. Creative software covers photo editors, video makers, and design programs. Communication apps handle email, messaging, and video calls. Utility software performs maintenance tasks like backing up files or scanning for viruses. Entertainment apps stream video, play games, or listen to music. A single device can run dozens of applications at once, though running many at the same time slows performance because they all compete for your device's memory and processing power.
Key Takeaways
- Applications are programs that perform specific tasks, separate from your operating system, which manages the device itself.
- Common types include productivity tools (word processors, spreadsheets), creative software (photo and video editors), communication apps (email, messaging), and entertainment programs (streaming, games).
- Applications run on top of the operating system and use it to access your device's hardware like the screen and storage.
- You install applications from official sources like the App Store, Google Play, or the software maker's website, and they take up storage space on your device.
How applications differ from your operating system
Your operating system (Windows, macOS, iOS, or Android) is the foundation software that runs your device. It manages everything behind the scenes: how your hardware works, how files are stored, how programs communicate with each other. You do not directly use the operating system for tasks — you use applications that run on top of it.
Think of it this way: the operating system is like the engine and controls of a car, while applications are the tools you use inside it. You do not interact with the engine to drive; you use the steering wheel, pedals, and buttons. Similarly, you do not open your operating system to write a letter; you open a word processor application. The operating system handles the technical details in the background so the application can focus on what you want to accomplish.
Where applications come from and how you install them
Most applications come from official stores tied to your device's operating system. On iPhones and iPads, that is the App Store. On Android phones and tablets, it is Google Play. On Windows computers, you can use the Microsoft Store, but many applications are also downloaded directly from the software maker's website. On Mac computers, the App Store exists, but many programs are also installed from the developer's website or through a package manager.
When you install an application, it takes up storage space on your device — anywhere from a few megabytes for a simple tool to several gigabytes for complex programs like video editors or games. Installation usually involves clicking a download button, confirming you want to install it, and waiting for the process to finish. Some applications require you to create an account or sign in before you can use them. Once installed, the application appears in your applications menu or on your home screen, ready to open whenever you need it.
How applications use your device's resources
Every application running on your device uses a portion of its memory (RAM) and processing power (CPU). When you open an application, the operating system loads it into memory and gives it access to the resources it needs. If you open many applications at once, your device has to divide its resources among them, which can make everything run slower.
Applications also use your device's other hardware. A camera app uses your camera. A music app uses your speakers. A maps app uses your GPS and internet connection. Some applications run in the background even when you are not actively using them — for example, a messaging app might check for new messages every few minutes. This background activity uses battery power on phones and tablets, which is why closing unused applications or turning off background activity in settings can extend battery life.
Free applications versus paid applications
Applications are sold or distributed in different ways. Free applications cost nothing to download and use. Some are truly free with no catches — the developer simply offers them as a service. Others are free but show advertisements, which is how the developer makes money. Still others are free to download but charge you for advanced features (called a "freemium" model).
Paid applications require you to pay a one-time fee before you can download them, usually ranging from a few dollars to tens of dollars depending on complexity. Some applications use a subscription model, where you pay a monthly or yearly fee to keep using them — Microsoft Office 365, Adobe Creative Cloud, and many streaming services work this way. Subscription applications often stop working or become limited if you stop paying, whereas a one-time purchase usually lets you keep using the application indefinitely (though you may not receive updates).
Updates and maintenance for applications
Software developers regularly release updates to applications. Updates fix bugs (problems in the code), add new features, improve performance, or patch security vulnerabilities. Most applications check for updates automatically and notify you when one is available. You can usually choose to install the update immediately or delay it, though delaying too long leaves your device exposed to security risks.
Some applications become outdated and are no longer maintained by their developer. If an application stops receiving updates and a security problem is discovered, using it becomes risky. Developers sometimes also discontinue applications entirely, which means they stop working on newer versions of the operating system. This is why it is worth checking whether an application you rely on is still actively maintained before you invest time learning it.
Frequently Asked Questions
What is the difference between an app and software?
The terms are often used interchangeably. "App" is short for application and usually refers to smaller, single-purpose programs (like a calculator or weather app). "Software" is a broader term that includes applications, operating systems, and other programs. For practical purposes, they mean the same thing when someone says "I need to download an app" or "I need to install software."
Can I run the same application on my phone and computer?
Not always. Applications are built for specific operating systems. An app written for iPhone will not run on Android, and a Windows program will not run on a Mac without special tools. Some developers release versions of their application for multiple platforms (like Microsoft Word for Windows, Mac, iPhone, and Android), but you have to download the version made for your device.
What happens if I uninstall an application?
Uninstalling removes the application and frees up the storage space it used. Your files created in that application usually remain on your device unless you delete them separately. If you uninstall a subscription application, you lose access to it until you reinstall and pay again. You can always reinstall a free or paid application you purchased from the official store.
Do I need to close applications when I am not using them?
On modern devices, closing applications is less critical than it used to be because operating systems manage memory efficiently. However, closing applications you are not using can help preserve battery life on phones and tablets, especially if they run background processes. On computers, closing unused applications frees up memory and can improve overall performance.
Why do some applications need permission to access my camera or location?
Applications request permission to access sensitive hardware or data for security reasons. A maps application needs your location to show where you are. A video chat application needs your camera and microphone. Your operating system requires the application to ask your permission first, rather than allowing it automatic access. You can usually change these permissions in your device's settings if you want to revoke access.