--- title: "Computing Fundamentals" description: "16 topics in Computing, in the order they build on each other." canonical: https://lightmysky.com/learn/computing/areas/computing-fundamentals source: https://lightmysky.com/learn/computing/areas/computing-fundamentals.md retrieved: 2026-10-19 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Computing Fundamentals 16 topics in Computing, in the order they build on each other. Page: https://lightmysky.com/learn/computing/areas/computing-fundamentals - [Simple Programs: Sequences and Instructions](https://lightmysky.com/learn/computing/simple-programs-sequences-and-instructions-mt_IUvBwahibH): Write, run and fix simple programs by putting instructions in order: plan a sequence of steps, predict what the program will do before running it, and hunt down the step that went wrong when it doesn't behave as expected - [Creating Digital Content](https://lightmysky.com/learn/computing/creating-digital-content-mt_dfhHVURsn6): Use technology purposefully to create and manage digital work: write and edit documents, make pictures, slides and simple videos, save files where they can be found again, and choose or combine the right software for the job - [Networks and the Internet](https://lightmysky.com/learn/computing/networks-and-the-internet-mt_JmrMg6v8V_): Connected computers can share information. The internet is a network of networks. Services such as the world wide web, email and video calls use it to pass data from machine to machine. - [Programming with Loops and Variables](https://lightmysky.com/learn/computing/programming-with-loops-and-variables-mt_9x5zgShXPg): Design and debug programs that use repetition, selection and variables: repeat actions with loops, branch with if-blocks, keep score in a variable, and break a bigger problem into smaller parts that can be programmed one at a time - [Searching and Evaluating Online](https://lightmysky.com/learn/computing/searching-and-evaluating-online-mt_S-XboPwA8k): Search the web effectively and judge what comes back: choose precise search words, understand that results are selected and ranked by a program rather than checked by a person, and weigh whether a page is trustworthy and relevant - [Events: Programs That React to What the User Does](https://lightmysky.com/learn/computing/events-programs-that-react-to-what-the-user-does-mt_HFtGUhZHz4): A program does not have to run from top to bottom. A handler sits waiting for a click, a key press or a collision, and runs only when that thing happens. - [Conditions That Combine: And, Or and Not](https://lightmysky.com/learn/computing/conditions-that-combine-and-or-and-not-mt_ZYdtXQZy5r): One test is often not enough. Joining tests with and, or and not lets a single decision depend on several things at once, and each joiner changes when the branch is taken. - [Inside the Box: Input, Processing, Storage and Output](https://lightmysky.com/learn/computing/inside-the-box-input-processing-storage-and-output-mt_Oms8067Pnm): Every computer, from a phone to the controller in a washing machine, does the same four jobs: take data in, work on it, keep it, and send results out. Naming which part does which job explains what any device is. - [Random Numbers and Programs That Differ Each Run](https://lightmysky.com/learn/computing/random-numbers-and-programs-that-differ-each-run-mt_t8GTOW3hyN): A random value makes a program behave differently every time it runs. That is what games and simulations need, and it changes what counts as having tested the program. - [Finding a Bug by Changing One Thing at a Time](https://lightmysky.com/learn/computing/finding-a-bug-by-changing-one-thing-at-a-time-mt_DMgajrUSy_): Changing several things at once hides which change mattered. Working one change at a time, with a prediction written down before each run, finds the fault and says what caused it. - [Why a Computer Works with Only Two Symbols](https://lightmysky.com/learn/computing/why-a-computer-works-with-only-two-symbols-mt_r0wLIjpi5R): Inside the machine every value is a pattern of switches that are either on or off. Two states can be told apart reliably in a circuit, which is the reason a computer counts in twos rather than tens. - [An Agreed Code: How the Same Bits Mean Letters or Colours](https://lightmysky.com/learn/computing/an-agreed-code-how-the-same-bits-mean-letters-or-colours-mt_IQY-PHtZVZ): A pattern of bits means nothing on its own. It becomes a letter, a colour or a note only because a code says so, and both ends have to be using the same code. - [Addresses on a Network: IP Addresses, Hostnames and Paths](https://lightmysky.com/learn/computing/addresses-on-a-network-ip-addresses-hostnames-and-paths-mt_tGgw0Vhd8b): IP addresses identify destinations for network data. Ordinary devices on one local network need distinct addresses, while separate private networks can reuse them. A web address contains a hostname and a path. DNS can look up IP addresses for the hostname. - [Reading a Program Someone Else Wrote](https://lightmysky.com/learn/computing/reading-a-program-someone-else-wrote-mt_VdxhuxjBSn): Most code a person meets was written by somebody else. Working out what an unfamiliar program does, and then changing it on purpose, is a different skill from writing one from a blank screen. - [Spotting a Mistake in Stored or Sent Data](https://lightmysky.com/learn/computing/spotting-a-mistake-in-stored-or-sent-data-mt_wKwax55eo-): Data gets corrupted on the way, so systems send extra bits that only fit when nothing has changed. A parity bit or a check digit catches an error without anybody reading the message. - [Writing an Algorithm Down: Flowcharts and Pseudocode](https://lightmysky.com/learn/computing/writing-an-algorithm-down-flowcharts-and-pseudocode-mt_RCm-4b4Lof): An algorithm can be recorded before any code exists, as a flowchart or as pseudocode. Both fix the order, the decisions and the repetitions, so the plan can be checked on paper and argued about with someone else.