The difference between hardware and software
The most basic distinction in computing is between hardware and software. Grasping it makes it easier both to choose a device and to know where to look when something stops working.
Short answer
Hardware is the physical part of a device that you can touch: screen, processor, memory, keyboard. Software is the whole body of instructions and programs telling those parts what to do: the operating system, apps, games. Hardware is the body; software is the set of instructions running it.
What is hardware?
Hardware is every physical component of a device. Your phone's screen, camera and battery; your computer's processor, memory, drive, keyboard and mouse are all hardware. Items connected from outside, such as a printer, modem or headphones, are called peripherals, and they too are hardware.
What marks hardware out is its physicality: it is manufactured, fitted, worn out, broken and replaced. A piece of hardware cannot decide anything on its own; it needs instructions telling it what to do.
Modern devices add less visible members to the hardware list: receivers that establish position, sensors that detect movement, fingerprint readers and face recognition cameras. The screen rotating when you turn your phone, or your step count being recorded, are everyday examples of these small parts working hand in hand with software.
What is software?
Software is the set of instructions that tells hardware, step by step, what to do. You cannot hold it; it sits on a drive as data and is carried out by the processor when it runs. The messaging app on your phone, the office program on your computer, a website and games are all software.
The most fundamental layer of software is the operating system: Windows, macOS, Android, iOS. It manages the device's resources and provides the ground on which other applications run; you can read more in the operating system guide. Software does not wear out, but it does fall out of date, which is why it is updated.
How the two complete each other
Neither works alone. A computer without software is a box with the power on and nothing to say; software without hardware is a list of instructions with nowhere to run. When you press a key, the keyboard (hardware) produces a signal, the operating system (software) interprets it, and the application shows the letter on screen.
There is also a layer in between: firmware. Embedded inside devices such as modems and smart televisions, this small piece of software governs the hardware's basic behaviour, and it too is updated from time to time.
Is the fault in the hardware or the software?
The most practical everyday use of this distinction is troubleshooting. A rough test: if the problem appears the same way in every situation and every program, hardware becomes more likely; if it happens only in one particular application, software is the stronger candidate.
A coloured line permanently fixed on the screen, for instance, is very probably a hardware fault, whereas a single app closing as it opens is a software one. Simple steps such as restarting and updating resolve a good share of software-related problems; where hardware is suspected, service support is the better address.
There are practical ways to test the split: try the same task in a different program (does the document also refuse to open elsewhere?), connect the device to a different network or cable, and if possible repeat the task in another user account. If the problem persists identically every time, hardware becomes more likely; if it changes with the conditions, software does.
What the distinction is worth when buying
A device's hardware is the part hardest to change afterwards; the processor, memory and storage have to be chosen correctly at purchase. Knowing the difference between memory and storage is particularly useful here, and the guide to RAM and storage covers it.
On the software side the question is this: how long will this device keep receiving updates? A device whose update support has ended starts to weaken on security even if its hardware is sound. Length of software support deserves to be a purchase criterion alongside raw hardware power.
The same double view helps when buying second-hand: on the hardware side you check battery health, the screen and the casing; on the software side you confirm that the device still receives the current version and that the previous owner's accounts have been fully signed out. Neglect either side and a cheap device can turn out expensive.
Frequently asked questions
Are an app and software the same thing?
Every app is software, but software is the broader concept: operating systems, drivers and embedded programs are software too. An app is the kind of software you interact with directly as a user.
What exactly is firmware?
It is the small piece of software embedded in hardware that governs the basic behaviour of that component. It is found in devices such as modems, printers and smart TVs, and manufacturers publish firmware updates to fix bugs and security flaws.
If my phone has slowed down, is that a hardware problem?
Usually it is software-related: full storage, apps running in the background, or an out-of-date version. Freeing up storage and applying updates often helps, though hardware factors such as declining battery health can contribute as well.
Why does ageing hardware affect software?
New software versions generally ask for more resources. When older hardware struggles to meet that demand, the device feels slower; this is why manufacturers eventually stop offering new versions to older devices.
This guide draws on introductory computer science teaching material and the publicly available technical documentation of device manufacturers.