Layman's Guide to Computing

Time is synchronised from higher-precision sources through a protocol called Network Time Protocol (NTP). A public pool of time servers is available for synchronisation at pool.ntp.org.

To get your location using GPS, your phone receives information from four overhead GPS satellites: their location, and the distance between them and your phone. With this information, your phone can calculate its location.

nstead of GPS satellites, smartphones can also use wifi points and cell towers to determine their position (if enabled in the OS).

A content delivery network comprises multiple servers around the world that are able to quickly distribute static content (typically images and video) to viewers that request it. This avoids overloading the hosting server, which would otherwise have to serve data over the network, possibly through many intermediary hops.

Cross-site scripting attacks occur when a webpage loads malicious code from a third-party, usually carried out by a script in the page. Today, websites are protected from loading unauthorised scripts through cross-origin resource sharing (CORS) policy implemented in browsers, which only allows a website to load scripts from authorised domains.

Typeface families consist of multiple fonts for each style in the typeface. Each font consists of glyphs, which are mathematical shapes described by curves joining points. These shapes need to be rasterised for display on a computer screen, or for printing on paper. Font files usually come in .ttf, .otf, or .woff formats.

Software that we use usually comes from the OS makers, or from third-party developers. These two groups of developers are not the same, and might even have conflicting intentions and goals.

Linux software is distributed through Linux distros. The maintainers of distros maintain repositories of software that have been tested with the distro. Most users will access software in the distro’s repositories through a program called a package manager. So users have full control over when updates and new software should be installed.

There are easy and quick ways to check the validity of the most common advice for resolving system slowdown. But it still seems to happen even after these tips have been tried.

Caches speed up app operations by storing temporary data on the device’s storage. This assumes that access to storage is much faster than access to the file’s original source. On Android, users can clear an app’s cache, but not the system cache.

Fragmentation is likely a contributor of system slowdown, particularly for mobile devices: the databases used by most mobile apps tend to store data in many small chunks rather than fewer big chunks, which slows down data search operations. The most effective measure for improving device responsiveness is usually to clear the app cache, so the app does not attempt to read previous data from storage.

A search engine uses bots to build up a database of URLs and their contents. The search engine uses various algorithms to determine the most relevant results for a search request.

By better understanding how search bots categorise pages, a website owner can use keywords and other techniques to optimise the ranking of their page for specific search terms.