An introduction to Solid

Presentation given February 18th 2020 at a MyData meetup in Barcelona.

Outline & summary:

Slide 2. Who am I? Learn more at https://noeldemartin.com/.

Slide 3. What is Solid? Before getting into that, let's ask ourselves what is The Internet.

Slide 4. There are two ways to answer this: what is it in theory and what is it in practice. In theory we would say something like "The Internet is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to link devices worldwide" (Wikipedia). But in practice, the response depends on who answers.

Slide 5. Probably nobody in this room would say The Internet is any of these companies: GAFAM. However, the reality is that for some countries The Internet is one or the combination of these companies (see - https://seasia.yale.edu/myanmar-facebook-internet-and-internet-facebook). Even for many of us, The Internet is heavily influenced by these companies.

Slide 6. For the majority of people The Internet is synonymous with The Web. The web was created by Tim Berners-Lee on 1989. He introduced most of the technologies you already know: Browsers, HTML, HTTP, etc. One interesting fact is that it was conceived as decentralized technology. Something that is now becoming a hot topic, but The Web was already decentralized at the beginning.

Slide 7. In 1994 The W3C was formed to define the standards that would shape The Web, led by Tim Berners-Lee.

Slide 8. In 2001 The Semantic Web was introduced. Its vision was to include semantic definitions in web content so that machines would understand websites better. In contrast with the first generation of web technologies, you probably haven't heard of these: Linked Data, RDF, JSON-LD, etc. One interesting use-case were this is put to practice is in Social Media link previews. In this tweet, we can see that Twitter is understanding the content of the link and it's showing us some external information (image, title and description). This is achieved using The Open Graph protocol - https://ogp.me/ - which is based on Semantic Web technologies.

Slide 9. If we fast forward to 2020, we can see that the landscape of The Web is pretty grim. This image of The Internet Map from 2011 shows that most traffic has been colonized by a couple of companies.

Slide 10. At this point, I believe only 2 use-cases remain of decentralization in practice: Email and RSS. And it isn't a coincidence that I'm using Gmail's logo to represent email. Even though the technology is still decentralized, most people use Google services.

Slide 11. Back in 2014 Solid was started in the MIT. Its aim was to provide a framework where the ideas and technology of The Semantic Web were put in practice to develop applications. Hence Solid: Social Linked Data.

Slide 12. In 2018, Inrupt was founded by Tim Berners-Lee and John Bruce to push forward the Solid project and ecosystem.

Slide 13. Here's a recap of what's happened. Solid is the evolution of the vision that Tim Berners-Lee's had for The Web, and it isn't only one new hot technology that appeared 2 years ago.

Slide 14. So then, what is Solid?

Slide 15. Solid is a set of technologies and principles aimed at developing applications with an architecture that wants to: allow users to move data between services, reuse data across apps, connect with others regardless of the apps they are using and choose what you want to share instead of having others do it for you.

Slide 16. The most important concept introduced for users is data PODs: A place that you own where your data is stored. When you use a Solid application, the data will be sent to your POD, and you can access this data without the application. Data becomes decoupled from applications.

Slide 17. One important concept of how this is achieved is RDF vocabularies. Using the Resource Definition Framework (RDF), data can be described with standard definitions. There are some common vocabularies - https://schema.org being the most used - and you can also create your own.

Here's some examples of how a web using Solid would look like.

Slide 18. Instead of having data within data silos, you'd be able to access all your data from any application. This means applications could be tailored to different use-cases without having to own all your data.

Slide 19. A decentralized web would mean that the content you see when you browse it doesn't come from a central location. This is similar to the example of link previews in Social Media, but much more extreme. In this example the post is in the author's POD, and each like and comment is contained within their owner's POD. The content displayed on the website is an aggregate of multiple data sources.

Slide 20. Once applications are decoupled from data, services can compete on service quality and user experience instead of data ownership and vendor lock in. This also creates a new market where each user can choose storage providers that align with their privacy values.

Slide 21. How can you use Solid today? You need two things: a POD provider and Solid applications. You can find some POD providers at https://solid.inrupt.com/get-a-solid-pod - or host your own. And you can find some Solid applications at https://solidproject.org/use-solid/apps.