Software and operating systems
FoundationSoftware is the programs you cannot touch. The operating system (OS) is the manager running the whole computer; applications are the tools you use for tasks, like Word or Minecraft.
- Software = system software + applications
- The OS manages hardware and files, gives you an interface, runs apps
- Computer OS: Windows/macOS/Linux; phone OS: Android/iOS
§Text Passage
1Hardware is the body and software is the soul. Software falls into two families: system software manages the computer itself — operating systems such as Windows and macOS, together with drivers — while application software helps users accomplish real tasks such as writing documents, browsing the web, playing music and online shopping. Applications can only run on top of system software, and neither works without the other; without software, even the most expensive computer is an empty shell.
2The operating system (OS) works like the machine's head butler: it allocates memory, organises files and schedules programs to share the CPU, so you can play music and browse the web at the same time without interference. What a computer loads first after switching on is exactly the OS; without it the machine cannot even start and no application could be installed or run, which makes it the most basic and most important system software.
3Hong Kong example: MTR ticket machines and minibus Octopus readers run small embedded operating systems. When buying a new computer, look beyond the specifications at which OS it ships with and whether it suits the applications you use every day. Updating the system regularly to patch security holes, with automatic updates switched on, is another essential step in protecting your data and lowering the risk of infection or intrusion.
1Summary 重點摘要
Software is the programs you cannot touch. The operating system (OS) is the manager running the whole computer; applications are the tools you use for tasks, like Word or Minecraft.
2Vocabulary cards Vocabulary
Programs that tell the computer what to do — you cannot touch them.
The core software managing hardware, files and other programs, e.g. Windows, Android.
Software for a specific task, e.g. Word, Chrome, WhatsApp.
Using icons, windows and a mouse instead of typed commands.
A file is one piece of data (a photo, a document); folders organise files.
The process from pressing power until the OS loads and the desktop appears.
Software that runs the computer itself, including the operating system and drivers.
A small program that lets the OS control a piece of hardware, e.g. a printer driver.
3Step by step Steps
- Two kinds of softwareSoftware falls into two families by purpose: system software manages the computer itself, including the operating system and drivers; application software helps the user do real tasks such as writing documents, playing music, browsing the web and shopping online. The first is the foundation for the second — without system software, applications cannot even open, just as a building cannot stand without foundations. A common error is calling the browser system software; Chrome is an application for going online and must be installed on top of an operating system.
- Four jobs of an OSAn operating system does four core jobs. First, manage hardware: allocate memory and schedule programs to take turns using the CPU. Second, manage files: store and organise data in an orderly way. Third, provide the user interface: desktop, icons and windows make the machine easy to operate. Fourth, run applications: every app relies on the OS to allocate resources before it can open. Think of the OS as the machine's head butler — playing music while browsing the web without interference is exactly its behind-the-scenes coordination.
- Common operating systemsComputers commonly run Windows, macOS or Linux; phones run Android or iOS. Applications are not directly interchangeable between operating systems — an iPhone cannot run Windows programs, because each OS provides a different running environment and programs must be rewritten or ported for it, so pick the version matching your device when downloading. A common exam task is to name the OS of a device: a Windows laptop runs Windows — not Chrome, and not Word.
- The boot processAfter pressing the power button, the hardware automatically checks its parts, then the operating system loads from the disk into RAM, the desktop appears, and only then can applications open. The whole process is called booting and usually takes a few dozen seconds. The order cannot be swapped: the OS must load first, because applications all depend on it for resources. A common mistake is thinking apps open before the OS loads — the order is exactly the reverse, and it is a favourite flowchart ordering question.
- One question to tell them apartTo tell an operating system from an application, ask one question: without it, could the computer still start? Without an OS it cannot start at all; missing one application changes nothing. With this test the answer is instant: Windows and Android are operating systems; Paint and Calculator are applications. The question is especially useful in exams — for 'which of the following is not an operating system', apply the test to each option and the answer appears quickly and reliably.
- Two kinds of user interfaceUser interfaces come in two kinds. A GUI (graphical user interface) uses icons, windows and mouse clicks — intuitive and easy to learn, like the Windows desktop or a phone's home screen. A CLI (command-line interface) uses typed text commands — fast and precise, favoured by professionals, e.g. the Command Prompt in Windows. Modern operating systems usually provide both. For example, icons make a GUI clear at a glance for beginners, while an administrator can finish huge amounts of work with one CLI line. In answers, give both names, their features and an example.
4Diagrams Diagrams
5Worked example Example
Example: which are operating systems and which are applications? Windows, Chrome, Android, Photoshop, iOS.
- Apply the test to each item: without it, could the computer or phone still start and run? Whatever already loads at boot and manages the whole device is an operating system.
- Windows manages a computer's booting, hardware and files; iOS manages the iPhone; Android likewise runs the phone — so all three are operating systems.
- Chrome browses the web and Photoshop edits photos; both must be installed on top of an OS before they can open, so both are applications.
- Give a reason for every item, e.g. 'Chrome is an application because it must be installed on an OS to do one job — browsing the web'.
- Answer: Windows, Android and iOS are operating systems — they load at boot and manage the hardware, files and applications. Chrome and Photoshop are applications — they must be installed on an OS and each does one job, browsing the web and editing photos. The rule: whatever already runs at boot and manages the whole machine is the OS; everything else that does a specific task is an application.
6Common mistakes Mistakes
7Quick check Quick check
Q1Which is an operating system? A. Word B. Android C. Minecraft
Q2Name any two jobs of an operating system.
Q3Why can no app run without an OS?
Q4Can a Windows program be installed directly on an Android phone? Why?
Q5What does a driver do? Give one example.
8Recap Recap
- Software = system software + applications
- The OS manages hardware and files, gives you an interface, runs apps
- Computer OS: Windows/macOS/Linux; phone OS: Android/iOS
- No OS, no boot; a missing app changes nothing
- The OS is the manager: allocating memory and sharing the CPU between programs