Whether it’s the future of finance or history’s biggest <a href="https://www.cnbc.com/2021/04/23/bitcoin-a-gimmick-and-resembles-a-ponzi-scheme-black-swan-author-.html">Ponzi scheme</a>, use of content about cryptocurrency is up 271%, with content about the cryptocurrencies Bitcoin and Ethereum (ether) up 166% and 185% respectively. General content about blockchains is up 78%, and from a much higher starting point (reflecting the fact that our audience has more developers than speculators). <a href="https://www.hyperledger.org/">Hyperledger</a>, a collection of blockchain technologies that targets enterprise markets, is up 66%. Our data doesn’t tell you whether to buy bitcoin or ether, but it does show a huge increase in interest.

Cryptocurrency and Blockchain

The programming languages Go and Rust continue to grow. Usage of content about Go is up 23% since last year, and Rust is up 31%. This growth continues a trend that we noticed last year, when Go was up 16% and Rust was up 94%.   Both Rust and Go are here to stay. Rust reflects significantly new ways of thinking about memory management and concurrency. And in addition to providing a clean and relatively simple model for concurrency, Go represents a turn from languages that have become increasingly complex with every new release.

Programming Languages

Web3 is a collection of ideas about a “next generation” web that’s designed so that it can’t be dominated by a small number of gigantic platforms, like Facebook and Google. Web3 proponents typically mix decentralized protocols like the InterPlanetary File System (<a href="https://en.wikipedia.org/wiki/InterPlanetary_File_System">IPFS</a>) with blockchains and NFTs to make content immutable and ownable. As with NFTs, no content in our platform has “Web3” in the title. But we’ve seen a 343% increase in the number of searches for the term—again, from a small starting point.

Web3

Software architecture, Kubernetes, and microservices were the three topics with the greatest usage for 2021. Their year-over-year growth is also very healthy (19%, 15%, and 13%, respectively). It only looks small when compared with the growth of topics like <a href="https://www.redhat.com/en/topics/api/what-does-an-api-gateway-do">API gateway</a> (218%). That kind of growth reflects the “law” we’ve observed throughout this report: it’s easy for a small topic to have large growth numbers but much more difficult for a topic that’s already dominant. API gateway content gets roughly 1/250 as many units viewed as content on architecture or Kubernetes does.

Software Development

Security was frequently in the news in 2021, and for the worst possible reasons. A wave of ransomware attacks crippled important infrastructure, hospitals, and many other businesses, both large and small. Supply chain attacks, in which an attacker places a payload in software that’s delivered to its victim through normal distribution channels, occurred in both open source and commercial software.  We saw large increases in content about specific topics within security. Usage of content about ransomware has almost tripled (270% increase).

The Growing Importance Of Security

Ignoring stop words (like “and”) and significant words that aren’t really meaningful to us (like “good”), the top five words were “data,” “Python,” “Git,” “test,” and “Java.” (And you can see most of the words from those top two questions in the top 15 or 20 words.)What can we learn from this? Data continues to be one of the most important topics for our users.

The Learning Platform Data Analysis

Quantum computing remains a topic of interest. Units viewed is still small, but year-over-year growth is 39%. That’s not bad for a technology that, honestly, hasn’t been invented yet. Although some primitive quantum computers are available now, computers that can do real work are still several years away. (<a href="https://research.ibm.com/blog/ibm-quantum-roadmap">IBM’s roadmap</a> has 1,000-physical-qubit computers coming in two years, though the best estimate is that we’ll need 1,000 physical qubits to create one <a href="https://singularityhub.com/2021/07/19/google-gets-one-step-closer-to-error-corrected-quantum-computing/">error-corrected qubit</a>.) But when those computers arrive, there will clearly be people ready to program them.

Quantum Computing

We’ve also seen increases in content about the tools used to deploy software. Git is up 44%, Kubernetes is up 15%, Docker is up 5%, and Terraform is up 6%. Kubernetes led all topics in this category in units viewed. Furthermore, the two most popular Kubernetes certifications, Certified Kubernetes Application Developer (CKAD) and Certified Kubernetes Administrator (CKA), were up 24% and 13%, respectively.Three tools are sharply down: Chef, Puppet, and Ansible (27%, 38%, and 20%).

Software Deployment Tools

The term “metaverse” hasn’t shown up in any titles, though there’s a sharp increase in the number of searches for it (489%). And content about <a href="https://www.w3.org/TR/webxr/">WebXR</a>, a vendor-neutral standard for rendering 3D content on VR- and AR-capable devices (in addition to pedestrian 2D devices), is now starting to show up. (VRML, an older standard, has vanished from view.) No content on WebXR was available in 2020, but some has appeared in 2021, and searches for “WebXR” have increased by 168%.

Virtual Reality, Augmented Reality, and the Metaverse

Natural language processing has been very much in the news. As was the case for machine learning, usage of content with “natural language processing” in the title hasn’t changed much (up 3%); the abbreviation “NLP” is up 7%. Again, we can look at some of the new techniques that have made the news. The platform had no content on Transformers, BERT, or GPT back in 2020. All three are now coming onto the map. Similarly, there’s currently no content on <a href="https://copilot.github.com/">GitHub Copilot</a>, which uses the GPT-3 model to translate comments into working code, but we expect it to be a strong performer in 2022.

Natural Language Processing

You can’t talk about machine learning without talking about data and databases. It’s no surprise that, when we look at content usage, Oracle is leading the pack. It’s also no surprise that Oracle’s growth is slow (5%); as we often observe, rapid growth is most often associated with smaller, newer topics. Usage of content about the open source MySQL database (now owned by Oracle) is roughly 1/4 as high and has grown substantially (22%).

Databases

The core technologies for web programming have been very stable over the last two years. Usage of content about core components HTML, CSS, and JavaScript is almost unchanged (up 1%, up 2%, and down 3%, respectively). If Java and Python are table stakes for enterprise and data developers, so much more so are HTML, CSS, and JavaScript for frontend developers. They’re the foundational technologies for the web. If you’re not fluent with them, you’re not part of the conversation.

Stable as the Web

Our data about the cloud and cloud providers tells an interesting story. It’s clear that Amazon Web Services’ competition is on the rise. Usage of content about Microsoft Azure is up 32% and Google Cloud is up 54%, while the usage of AWS-related content has declined by 3%. Actual usage of content about Azure almost matches AWS, while Google Cloud is farther behind, although that may reflect the quantity of material available.Usage of content about hybrid clouds and multiclouds is still small, but growing very fast (145% and 240%, respectively).

Learning About the Cloud

We saw substantial increases in the use of titles with the words “observability” (up 124%), “container” (137%), “CI/CD” (109%), “monitoring” (up 36%), and “testing” (16%). A 36% increase for monitoring is very healthy, but the much larger increase for observability shows that this concept is winning people’s hearts and minds. Observability ultimately boils down to the ability to find the information you need to analyze a system’s behaviour, while monitoring refers to logging and watching certain pre-configured parameters that indicate the system’s health.

Operations, DevOps, and SRE

Among the newer frameworks and meta frameworks, Svelte seems to be thriving (up 71%, though from a very low starting point), while interest in Vue and Next.js seems to be fading (down 13% and 13%). Svelte may become a challenger to the more widely used frameworks in a few years if this keeps up. There was surprisingly little interest in Jamstack. That may be because the term rarely appears in the title of books or training, though searches for the term “Jamstack” were also infrequent.

Meta Frameworks

Usage of content with “machine learning” in the title is flat year-over-year (down 1%, which is noise). Usage of content with “ML” in the title is up 35%. We don’t expect another AI winter—AI is too solidly entrenched in online business practices, and in ways that aren’t as visible as social media recommendations; you’ll never know (or care) whether the company that makes your espresso machine is using machine learning to optimize the manufacturing process and manage inventory, but if they aren’t now, they will be.

AI, Machine Learning(ML), and Data

Words about cryptocurrency (“Bitcoin,” “Ethereum,” “crypto,” “cryptocurrency,” “NFT”) are further down on the list, though still in the top 20%. That’s not surprising. Elsewhere, we’ll see that the use of content about these topics is rising sharply, but usage still isn’t large.  The fact that these terms are appearing in significant numbers is certainly important.

The New Entrants

What O'Reilly Learning Platform Usage Tells Us About Where the Industry Is Headed