Layman's Guide to Computing

Status update

June 18, 2022

It’s been a good one-month break, so I figured it’s a good time to post some new updates! To new subscribers: hello! 👋 this newsletter was active on a weekly...

[LMG S13] Issue 169: Search engine optimisation

April 23, 2022

Previously: 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...

[LMG S13] Issue 168: Search engines

April 16, 2022

Previously: Fragmentation is likely a contributor of system slowdown, particularly for mobile devices: the database used by most mobile apps tend to store...

[LMG S13] Issue 167: Database fragmentation

April 9, 2022

Previously: 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...

[LMG S13] Issue 166: A cause of system slowdown: caches

April 2, 2022

Previously: 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...

[LMG S13] Issue 165: The myths of system slowdown

March 26, 2022

Previously: Linux software is distributed through Linux distros. The maintainers of distros maintain repositories of software that have been tested with the...

[LMG S13] Issue 164: Linux, the universal operating system

March 19, 2022

Previously: 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...

[LMG S13] Issue 163: System & software ecosystems

March 12, 2022

Previously: Typeface families consist of multiple fonts for each style in the typeface. Each font consists of glyphs, which are mathematical shapes described...

[LMG S13] Issue 162: Fonts

March 5, 2022

Previously: 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,...

[LMG S13] Issue 161: Security and XSS

February 26, 2022

Previously: A content delivery network comprises multiple servers around the world that are able to quickly distribute static content (typically images and...

[LMG S13] Issue 160: CDNs and content distribution

February 19, 2022

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

[LMG S13] Issue 159: Wifi & cell tower location tracking

February 12, 2022

Previously: To get your location using GPS, your phone requests information from four overhead GPS satellites: their location, and the distance between them...

[LMG S13] Issue 158: GPS

February 5, 2022

Previously: Time is synchronised from higher-precision sources through a protocol called Network Time Protocol (NTP). A public pool of time servers is...

[LMG S13] Issue 157: NTP and time-syncing

January 29, 2022

Previously: To speed up execution and avoid translation overhead, some systems employ ahead-of-time translation, storing the translated instructions to be...

[LMG S12] Issue 156: Translation

January 22, 2022

Previously: Translating a set of instructions before executing it will always lead to a slowdown, although sometimes this may not be noticeable to users. So,...

[LMG S12] Issue 155: Emulation performance

January 15, 2022

Previously: Programs that were not compiled for the instruction set of the host OS have to go through an emulation layer program. This program translates the...

[LMG S12] Issue 154: Emulation

January 8, 2022

Previously: The cloud offers standard digital business services, accessible through a web interface and API, which any developer (with a credit card) can...

[LMG S12] Issue 153: Using the cloud

January 1, 2022

Previously: Actually making a web application requires you to set up lots of supporting software and carry out lots of steps to create a suitable app...

[LMG S12] Issue 152: Getting started with programming

December 25, 2021

Previously: The Java Runtime Environment (JRE) bundles the Java VM and supporting libraries. The JRE has to be installed on the user’s system for Java...

[LMG S12] Issue 151: the Java VM

December 18, 2021

Previously: System VMs provide a set of virtualised hardware that the OS interacts with. Process VMs provide a set of libraries that a program (written in...

[LMG S12] Issue 150: System VMs vs Process VMs

December 11, 2021

Previously: Containers are one layer of virtualisation above virtual machines: containerisation systems virtualise access to the operating system, presenting...

[LMG S12] Issue 149: History of commercial computing - containerisation

December 4, 2021

Previously: Renting out virtual hardware instead of physical hardware meant that instead of having to move hardware around and manage it, you could send the...

[LMG S12] Issue 148: History of commercial computing - cohosting

November 27, 2021

Previously: Running a virtual machine is like running a physical machine, but within a window in your OS. Co-located hosting A not-so-long time ago, to run a...

[LMG S12] Issue 147: Operating systems on virtual hardware

November 20, 2021

Previously: Virtual hardware can be created in the form of drivers that respond to a program’s requests for hardware resources. If a bootup program...

[LMG S12] Issue 146: Virtual hardware

November 13, 2021

Previously: Programs do not usually deal with the gnarly details of hardware, but instead access it through an interface. They access storage devices through...

[LMG S12] Issue 145: What an app wants, what an app needs

November 6, 2021

Previously: In 1999, VMware launched VMware Workstation, which allowed multiple operating systems to run off a single machine. In Season 5 (Issue 53), I went...

[LMG S12] Issue 144: Programs-in-a-vat

October 30, 2021

Previously: The Apple M1 is a souped-up iPhone processor, with unified memory. I want to circle back to talking about processors again in this season,...

[LMG S11] Issue 143: Implications (Part 2) – Future Goals

October 23, 2021

Previously: Using the same hardware for both smartphones and laptops would make it much easier to write apps for both platforms. The closer they are in...

[LMG S11] Issue 142: Implications (Part 1) - Software

October 16, 2021

Previously: The Apple A14 and Apple M1 are essentially the same chip architecture: they use almost the same building blocks, just with different numbers of...

[LMG S11] Issue 141: The Apple A14 and M1

October 9, 2021

Previously: Shared memory is easier to implement when a company has control over the designs of both CPU and GPU. So, to recap: Most companies design either...

[LMG S11] Issue 140: The shared memory dream

October 2, 2021

Previously: Around 2015, the high-performance computer industry quickly realised that this would be much more efficient if the CPU and GPU could share the...

[LMG S11] Issue 139: What’s before this line is mine, what’s after this line is yours

September 25, 2021

Previously: A system-on-chip (SoC) combines the core functionality of a system—processing, graphics, memory, and control—into a single chip package. I am...

[LMG S11] Issue 138: System-on-Chip (SoC)

September 18, 2021

Previously: The M1 goes one step further: not only does it make do with fewer chips, it does so with passive cooling. In Issue 136, I showed the...

[LMG S11] Issue 137: The M1 Macbook Air

September 11, 2021

Previously: Slim laptops have been undergoing a gradual transition: more and more of their chips are no longer available as a replaceable card, but instead...

[LMG S11] Issue 136: The mobile workstation – laptops

September 4, 2021

Previously: A modern CPU is manufactured through a process called photolithography, by which the CPU components are etched onto the silicon substrate by...

[LMG S11] Issue 135: Part 2 – Unifying the CPU and MCH (post-2008)

August 28, 2021

Previously: Light takes 0.3 ns to travel 10 cm, approximately the distance by wire between the CPU and the MCH. This potentially causes operations between...

[LMG S11] Issue 134: Part 1 – the Intel Core i-series launches!

August 21, 2021

Previously: The ATX form factor also brought with it a new breed of computers with more specialised chipsets: the memory controller hub (MCH) and peripheral...

[LMG S11] Issue 133: the ATX form factor (post-1995)

August 14, 2021

Previously: Chipsets served as go-betweens in the AT form factor by IBM. In 1993, Intel launched its Pentium line of processors; barely two years later, in...

[LMG S11] Issue 132: the AT form factor (pre-1995)

August 7, 2021

Previously: CPUs have limited throughput, since there is a max frequency they can operate at, and a limit to the number of wires they can be connected to...

[LMG S11] Issue 131: What do early CPUs and startup founders have in common?

July 31, 2021

Previously: AC power from the wall uses electric current that alternates directions, while DC power from batteries uses electric current that flows in one...

[LMG S10] Issue 130: Power limits

July 24, 2021

Previously: The larger the surface area, the faster an object loses heat. The larger the temperature difference between an object and its surroundings, the...

[LMG S10] Issue 129: Cooling

July 17, 2021

Previously: Upgradable parts need a slot or socket to be inserted into; these slots/sockets need to be made robust enough, causing them to take up more space...

[LMG S10] Issue 128: Upgradeability

July 10, 2021

Previously: USB Power Delivery is a specification that describes how much voltage and current can be supplied by different categories of USB cables. It...

[LMG S10] Issue 127: USB Type-C Power Delivery

July 3, 2021

Previously: USB is a (licensed) technical standard that describes how devices connect to each other through a cable. USB Type-C is a new connector standard...

[LMG S10] Issue 126: USB Type-C

June 26, 2021

Previously: Analog formats such as VGA mostly contain the control signals that the CRT needs to operate, while digital formats such as HDMI and DisplayPort...

[LMG S10] Issue 125: Analog and digital conversion

June 19, 2021

Previously: The VGA video format originated in the time of cathode-ray televisions (CRTs). It was superseded by HDMI, a video format standardised by consumer...

[LMG S10] Issue 124: Video formats

June 12, 2021

Previously: Graphics cards contain lots of tiny cores that are much better at performing the same calculation for lots of decimal numbers. These cores are...

[LMG S10] Issue 123: Graphics cards: The Pixel Factory

June 5, 2021

Previously: Computers are general-purpose machines that usually process integer calculations. The graphics pipeline requires more specialised hardware that...

[LMG S10] Issue 122: The great flattening

May 29, 2021

Previously: 3D models are represented with vertices (points), edges (line segments between points), and faces in a computer. Images known as textures can be...

[LMG S10] Issue 121: In graphic detail

May 22, 2021

Previously: Driver files provide information about the driver, and instructions on how to receive information from the device, and encode information to be...