Machine Learning is a discipline within the broader field of Artificial Intelligence concerned with using insights from datasets to make predictions, classify new data points, and generate content. The algorithms used vary greatly in complexity and the real world applications that they are applicable to. Instead of concentrating on any particular a…

Abandonware is old software that is no longer commercially available. It's not a legal term, and in fact it's not legal to download most of the software that is termed "abandonware." In this episode we explain what abandonware is, the different legal situations that old software finds itself in, and we discuss whether or not downloading abandonware…

Grace Hopper is one of the most iconic people in the world of software. Her career as a mathematician, software innovator, computer science advocate, programmer, and technical leader spanned the early era of computing through to the 1990s. One of the first notable computer programmers, Hopper developed the first programming text book, one of the fi…

The creation of BASIC was one of the most important steps in the democratization of computing. BASIC, coupled with the Dartmouth Time Sharing System, was developed by math professors John Kemeny and Thomas Kurtz along with a team of undergraduate students at Dartmouth College in 1964. They revolutionized who could use and access a computer. In the …

Many large sophisticated machine learning models, like those employed in generative AI, are trained on immense amounts of copyrighted images or text. How is that legal? In this episode we delve into the exceptions to copyright law that enable such uses to not be seen by courts as infringement. This includes expressive vs functional uses of a copyri…

In 2020 the Trump administration and eleven state attorney generals initiated an antitrust lawsuit against Google for its alleged anti-competitive behaviors in the search engine market. Last month, the lawsuit went to trial. In this episode we explain what a monopoly is, the government's antitrust allegations, and weigh-in on whether we agree that …

Alphabet, the parent company of Google, is one of the largest companies in the world by market capitalization. But where does all of the revenue come from to support that? In this episode we analyze Alphabet's third quarter earnings report and earnings call. We delve into the different categories of revenue, how they breakdown as a percentage, what…

In this episode, originally published in 2020, we discuss the similarities and differences between iOS and Android. We delve into their history, business models, developer ecosystems, and user experiences. Does it really matter if you use iOS or Android? Listen to this episode and find out. Show Notes Episode 89: Multi-Touch Episode 99: Android App…

In software, a sandbox is an isolated environment that limits the resources that a particular application can access. Sandboxes are used to protect the security and privacy of the user. All Web apps and much consumer software running on modern operating systems like iOS, Android, macOS, and Windows runs in a sandbox. We also use our general definit…

We explain what caches are, and where they're typically used. We can think of a cache as a piece of temporary fast memory used for the retrieval of pre-computed expensive calculations or high latency resources. Caches can exist in hardware or in software. Beyond the CPU caches and web browser caches that most are familiar with, in this episode we a…

Hash tables are some of the most widely used and powerful data structures. They allow for the efficient storage of key-value pairs. Keys are identifiers that we want to lookup data by, while values are the actual data. Hash tables underly common abstract data types in programming languages used for key-value data known as dictionaries, maps, or ass…

Understanding open source licenses is critical if you're a software developer. What are your rights and responsibilities when you incorporate an open source library in your program? In this episode we explain why we have licenses, the different types of open source licenses, and best practices for an open source practitioner. Note that the licenses…

Shareware was a major distribution model for consumer software and games from the 1980s through to the 2000s. We’re privileged to be joined on the show by journalist and tech historian Richard Moss, the author of "Shareware Heroes: The renegades who redefined gaming at the dawn of the internet." In the most common scenario, a piece of shareware is …

We’re out this week, so we remastered a classic episode from 2020. It’s our third episode—a layperson’s introduction to bytes! Original description below: What is a Byte? In this episode we go down to the fundamentals and explain how data is represented in a computer. We discuss what a bit is, both at the hardware level and the software level. Then…

FreeBSD is probably the most popular operating system that most people have never heard of. Currently celebrating its 30th anniversary, FreeBSD is a performant, secure, Unix-like operating system with many advanced features that fills a lot of the same rolls as Linux, but is developed with quite different philosophical underpinnings. In this episod…

There are many misconceptions about open source software, even amongst those who think they understand it. In this episode we dispel five of the most common myths about open source software: Open Source Software is non-commercial Open Source Software is insecure Open Source Software is the same as public domain software Any piece of software that h…

ChatGPT and other tools based on large language models (LLMs) have taken the software world by storm. While their capabilities are incredible, they have also sparked a lot of fear, doubt, and hyperbole. In this episode we dispel five myths about ChatGPT and similar tools: 1. That they represent human-level intelligence 2. That they will cause wides…

Early video game consoles (1977-1994) had primitive hardware, no operating systems, and software that was distributed on ROM chips embedded in plastic cartridges. Yet, some of the most iconic gaming software of all time was developed on these systems. What programming language did they use? How did they work without a graphics library and operating…

We're travelling this week, so we remastered a classic episode from 2020. It's our second episode—operating systems explained for laypeople. Checkout the show notes below for other classic episodes about operating systems. Original description: This week we discuss the most essential layer of a computer’s software, the operating system. We describe…

How small can a programming language be and still be a programming language? In order for a programming language to be able to compute the same sorts of problems as any other language it must be Turing-complete. Amazingly, there is a programming language that has just eight commands, represented by eight single symbols, that is Turing-complete. In …

Strong passwords are so annoying to type-in and they're even more annoying to remember. Yet just about every modern website and app requires them. Why do we need special characters and numbers and different cases in every password we make? In this episode we explain how passwords are stored, and why a weak password stored securely is still a weak p…

An instruction set architecture (ISA) is a specification of the instructions that a microprocessor understands as well as the infrastructure necessary to support those instructions including registers and a way to communicate with memory. Each microprocessor that implements an ISA may differ in the specifics of its circuitry. But all of the micropr…

Go, a Google-backed programming language, is by some measures one of the ten most popular programming languages in the world. Although it's a general purpose language, it's also an opinionated one. The team of veteran language designers, highly influenced by C and disenchanted with C++, felt it was important to keep things simple. Since its launch …

Functional programming languages fit within a declarative paradigm and often have several key characteristics in common: immutable data types, pure functions, a distaste for global state, a preference for recursion over loops, first-class functions, and the liberal use of higher-order functions. We explain what these characteristics mean, why funct…

Last month marked the 40th anniversary of the Apple Lisa. The Lisa was an important evolutionary link in the history of the personal computer between the innovations at Xerox's PARC laboratory where the graphical user interface (GUI) was first conceived, and the modern GUIs that we are familiar with today. Released in 1983, the Lisa predated the Ma…

We're out sick this week, so we remastered our first ever episode. It's a little more general in scope than what we typically cover on the podcast, but we think it still holds up. We'll see you in two weeks! We define software. What is software? How is it different than hardware? What is the language of software? What are the different kinds of sof…

Mastodon is a social network currently attracting significant buzz in the tech world. A lot of its new users are part of an exodus from Twitter. But how does Mastodon differ from Twitter? It's open source, run by a non-profit, and uses a federated model. We explain why this matters and some of its downsides in this episode. Show Notes Mastodon Mast…

Different programming languages employ different memory management techniques. The most common are manual memory management, tracing garbage collectors, and reference counting. For the programmer, each of these techniques requires different levels of bookkeeping and causes a different trade-off between safety and performance. In this episode, we ex…

Mozilla is the entity that makes the Firefox web browser. It has an interesting corporate structure. The non-profit Mozilla Foundation has a for-profit subsidiary that does Firefox development. Much of Mozilla's revenue comes from an agreement with Google to be the default search engine within Firefox. In this episode we explore this arrangement an…

In the late 1990s, the open source software movement split from the free software movement. A rebranding, the open source movement has a less philosophical, or some may say moral, focus than the free software movement. Despite this, 99.9% of open source software is also free software according to their respective official definitions. In this episo…

Cross-platform mobile frameworks enable developers to write an app once and recompile it for both iOS and Android. This can reduce development costs, but there are some downsides. In this episode we discuss the differences between major cross-platform mobile frameworks and weigh their pros and cons. Show Notes Episode 104: Web Apps vs. Native Apps …

On January 19, 2038, certain non-updated legacy systems that use Unix time will roll their dates around to December 13, 1901. In Unix, time is recorded as the number of seconds since January 1, 1970. Because a signed 32-bit integer is used to record this value on many legacy systems, they will run out of seconds in 2038 (a signed 32-bit integer can…

When planning the development of a new app, one of the most basic questions to answer is whether to develop it as a Web app or as a native app. In this episode we delineate some of the pros and cons of each approach, including cost, accessibility, performance, capabilities, and more. We also discuss some alternatives like hybrid apps and cross-plat…

Expert systems are a sub-discipline within artificial intelligence concerned with creating problem solving programs based on machine-encoded human domain expertise. An expert system typically consists of a knowledge base, consisting of human-defined rules, and an inference engine that can run a problem through the rules. Expert systems were a very …

The PDF (Portable Document Format) file format has become ubiquitous in the computing world. PDF is a super format that can embed vector graphics, advanced typography, bitmap graphics, multiple compression technologies, fonts, encryption, interactive elements, and more. It is primarily used for creating documents that display exactly as they looked…

It is important to make software that is usable by all people, and that includes users with physical or mental challenges. Accessibility is about removing barriers, so that software can be used by everyone. In this episode we give a brief overview of accessibility in software. We emphasize the role that common sense good design plays, and explain h…

When it was released, the World Wide Web revolutionized communications and commerce. It was created by Tim Berners-Lee, who outlined its key technical achievements, philosophy, and insights in his 2000 book Weaving the Web. In this episode, we go over three of the key innovations explained in the book: networked hypertext, the URI, and decentraliza…

Android is the most popular operating system in the world, but developing apps for it can feel intimidating. In this episode we breakdown the Android development ecosystem—including the programming languages, frameworks, testing environments, and more. We approach the episode from the perspective of someone new to learning Android app development, …

It has long been debated whether Apple is more of a hardware company or more of a software company. In its quarterly reports it does not delineate between the two. Instead, it breaks its revenue into four big product categories and services. It cannot be pigeon-holed—it is a fusion of hardware, software, and services. Growth in services, in particu…

An Application Programming Interface (API) is a specification for how a piece of software provides functionality to other pieces of software. APIs can broadly be categorized into two categories: local and remote. Local APIs are provided by libraries from the operating system vendor or third parties. Remote APIs are specifications for how software o…

A BIOS (Basic Input/Output System) is a piece of firmware on a PC that sits between the hardware and the operating system. It takes care of some essential functions like hardware startup tests, power management, boot device order, and control of microprocessor support chips. The original firmware on IBM PCs and PC compatibles was called the "BIOS",…

The world of data stores has become complex and fragmented. Companies find their data spread across a variety of sources with no obvious way to integrate it. Estuary is a startup that is taming that complexity by making it easier to create real-time data pipelines. In this episode we speak with Johnny Graettinger, the co-founder of Estuary, about d…

There is a constant battle between software publishers and pirates who find ways to redistribute proprietary software in violation of its license. In this episode we explain how copyright law protects proprietary software, the mechanisms publishers employ to reduce piracy including forms of DRM, and the means pirates use to distribute software. We …

Your phone includes multiple technologies for tracking your location. Your location can be triangulated via signals to cell towers, precisely pinpointed using its GPS chip and a connection to a satellite, and approximated using WiFi signals and a big database of WiFi base station locations. In addition, an Indoor Positioning System like iBeacon can…

By several measures, including a 2021 survey by IEEE, Python is the most popular programming language in the world. But why? What's special about it? In this episode we'll go over Python's history, key technical aspects of the language, and the niches within software development that it dominates. We also discuss some problems in the Python world. …

Today we know PayPal as a financial powerhouse. But when it was a young company, it had to innovate to survive. PayPal was the result of the merger of two startups—Confinity and X.com. Confinity was trying to be a digital payments solution for Palm Pilots, while X.com was an early online bank. PayPal first found success as a conduit for eBay paymen…

Binary search is an algorithm for finding an item in a sorted data set. It requires that all of the items in the data set be of the same data type and comparable to one another. In other words, the data type needs to have a defined "order." Binary search is orders of magnitude more efficient than its chief alternative, linear search, which is just …

Every modern smartphone and tablet uses a multi-touch user interface. Multi-touch is a relatively recent phenomenon. While the earliest research into multi-touch took place in the 1960s and 1970s, it wasn't until Wayne Westerman and Fingerworks in the early '00s that the first modern multi-touch device was created. And it took the iPhone in 2007 to…

Human-Computer Interaction is a discipline at the intersection of computer science, psychology, and design. It's about making ergonomic interfaces that sit at the border between the human and the machine. In this episode we explain the field's history, what research in it entails, and its place alongside other disciplines. By the end of the episode…

A compiler is a program that takes source code written in a programming language and converts it into machine code that a microprocessor can understand. Compilers are sophisticated programs composed of several different phases including (but not limited to) tokenization, parsing, and machine code generation. In this episode we breakdown why compile…