# Computing - Hardware and Software > Source: https://ollybritton.com/notes/a-level/computing/topics/hardware-software/ · Updated: 2020-09-14 · Tags: computing, school, safe-to-post-online ##### What is hardware?? The physical, tangible parts of the computer. ##### What is software?? All the programs that make the computer function. You can't touch it. ##### What is the hardware part of a music CD?? The physical CD itself. ##### What are the two grooves in a CD called?? Pits and lands. ##### What do the pits and lands in a CD represent?? 0s and 1s. ##### What are the two types of software?? * Systems software * Application software ##### What is a peripheral device?? A secondary device used to get data in and out of software. ##### What are the 3 types of system software?? * Operating systems * Utility programs * Library programs ##### What is system software?? Software which runs and manages the computer's hardware and application programs. ##### Is peripheral management system software or application software?? System software. ##### Is a compiler system software or application software?? System software. ##### What is the role of the operating system in hardware and software?? The OS serves as a middle-man for communication between the computer's hardware and software. ##### What does WIMP stand for?? * Windows * Icons * Menus * Pointers (cursors) ##### What is utility software?? Software that maintains or optimizes a system. ##### What's some examples of utility software?? * Virus scanners * Automatic backups and restoration * File compression software * Disk defragmentation ##### What is disk defragmentation?? Putting all files and programs together so that they fit into continuous segments. ##### Why might a defragmented hard disk drive have better performance?? Because files and programs are placed sequentially, the OS can read files without having to jump to different sectors. This speeds up read/writes. ##### Why is some amount of free space needed to carry out disk defragmentation?? There needs to be space to put files while they are swapped in and out of place. ##### What is a library?? A library is a collection of pre-compiled routines that can be used by other programs. ##### What's an example of a Python library?? * `math` * `random` * `turtle` ##### What's the purpose of a library?? Programmers can invoke library functionality without having to re-write code. ##### What is bespoke software?? Software that is tailor made to one usecase. ##### Why is bespoke software often more expensive?? Because it has to be specially programmed for one use case. ##### Why might bespoke software be less future-proof than off-the-shelf software?? Off-the-shelf software is likely to get regular updates ##### What is an advantage of bespoke software?? Very specialised to a particular use case. ##### What is an example of application software?? * Word processors * Image editors * Accounting packages * Internet browsers * Email clients ##### What is the purpose of application software?? To allow users to complete different tasks. ##### What are the 4 categories of application software?? * General purpose software * Special purpose software ##### What is general purpose software?? Software which is used for multiple, generic purposes. ##### What's an example of general purpose software?? * Email clients * Browsers ##### What is special purpose software?? Software which performs tasks for a single, specific job. ##### Is presentation software general or specialised software?? General. ##### Is a calculator general of specialised software?? Specialised. ##### What are the two categories of bespoke software?? * Off-the-shelf * Bespoke ##### What's a benefit of off-the-shelf software?? * Likely to be more intuitive, well-tested & documented * Cheaper * Regular updates, future-proof ##### What's a drawback to off-the-shelf software?? * Might not do exactly what you need * Potentially more security vunerabilities ##### Why may off-the-shelf software be more vunerable?? Because it's easy for an attacker to get a copy of the software themselves. ##### What's a benefit of bespoke software?? * Does exactly what you want it to do. * Potentially less security vunerabilities ##### What's a drawback of bespoke software?? * Has to be made for one usecase: * Might be more expensive * May take a long time to develop * May not get regular updates * Less likely to be intuitive * Locked into an ecosystem --- Olly Britton — https://ollybritton.com. Machine-readable index: https://ollybritton.com/llms.txt