Applications and Software practice questions

Access control is the OS function that limits what each user account can do.

The OS signs each user in to an account and checks that account's permissions before allowing a file to be opened. That is access control. Device, disk and task management are other OS jobs: hardware, storage layout and running programs.

1. Identify what the OS is doing: deciding which user can open which files.
2. Separate the four management functions by what they manage: users' rights, devices, disks, running tasks.
3. Choose access control.

Exam tip: Deciding who can open, change or run something is access control.

OS types: mobile, desktop/workstation, server and embedded.

A smart thermostat does one job on small, limited hardware and the user cannot install general software on it. That is an embedded operating system. Mobile, desktop/workstation and server operating systems are general-purpose platforms for phones, personal computers and shared network services.

1. Note the device: a single-purpose appliance with limited hardware.
2. Recall which OS type is built into dedicated devices.
3. Choose embedded.

Exam tip: Dedicated devices such as thermostats, cameras and appliances run embedded operating systems.

A server OS provides services to many users across a network.

Providing shared files and centrally managed user accounts to hundreds of people is the job of a server operating system. A desktop OS is designed for one user at a workstation, and mobile and embedded systems serve a single device.

1. Note the requirement: shared files and accounts for many network users.
2. Recall which OS type provides services to clients.
3. Choose server.

Exam tip: Many users, shared resources, one network: a server OS.

Compression reduces the size of files and can pack several files into one archive.

Built-in compression (such as 'Compress to ZIP file' in Windows or 'Compress' in macOS) creates one archive holding the whole folder, usually smaller than the originals. Encryption protects data, indexing speeds up searches and defragmentation reorganizes a hard disk; none of them produce a single smaller file.

1. List the needs: one file, smaller size.
2. Match each feature to what it does to files.
3. Choose file compression.

Exam tip: Smaller and bundled into one file means compression, for example a .zip archive.

Encryption protects confidentiality by making data unreadable without a key.

Encryption transforms data so that anyone who copies or steals it sees only scrambled content unless they have the key. Compression saves space, the hidden attribute only removes a file from normal views, and read-only only prevents changes; none of these stop someone reading the data.

1. Recall what encryption does to the contents of a file.
2. Match each other option to its real feature: compression, hidden attribute, read-only attribute.
3. Choose the option about making data unreadable without a key.

Exam tip: Hidden and read-only files can still be read; only encryption makes data unreadable without the key.

File extensions tell the OS and user what type of data a file holds.

A .csv file stores table data as plain text, one row per line and commas between values, which is exactly the export described. .txt is plain text without a table structure, and .xlsx and .docx are application document formats rather than plain text.

1. Note the needs: plain text, comma between values, importable.
2. Recall what each extension stands for.
3. Choose .csv (comma-separated values).

Exam tip: .csv = comma-separated values: plain-text table data that most programs can import.