What is the relationship between RDF, RDFa, Microformats and Microdata

Question

I have done quite a bit of research, but I cannot understand the exact relationship between them. Also, now that the W3C has officially recognized RDFa, would you recommend it over Microdata, given that it matches Microdata and more?

Answer 1

<sarcasm> I can’t imagine what you find so confusing </sarcasm> (edit: these tags were invisible before)

Very briefly:

• Microformats A way to use html pages for both a human-readable document and machine-readable data without repetition (for example, gluing CSV in the head element).
• RDF A data model designed for the Internet. Schemaless uses URLs to indicate types and relationships.
• RDFa A method of encoding (writing) RDF in html, following the style of microformats (i.e. minimizing repetition). It works by adding several attributes to html.
• Microdata An alternative to RDFa using different attributes and a different data model.

Less briefly, RDF arose from attempts to make webby data. There was even a plugin for viewing the RDF predecessor of MCF (from Apple with curiosity). The data model has been designed so that you can write what you want without first setting up column names or key values ​​with everyone else on the Internet. RDF was standardly written (serialized) using XML (although other, more pleasant formats are available).

So in this world you can have a readable home page ( me.html ) and a data home page ( me.rdf ) for the machines you need to scoop up. These machines will not understand the meaning of <p>I live in <a href="http://example.com/Chicago">Chicago</a></p> , but they can use :me ex:livesIn <http://example.com/Chicago> if they search for "livesIn".

Microformats are also trying to make "webby" data, or maybe it should be web-y data. The insight here is that there is a lot of data on web pages, between prose. If you have a few tips, the machine may decide that this html fragment above is basically an address. These tips are microformats. They typically use conventions around html class names to indicate that the content is larger than the text.

Thus, microformats do not require a separate web page for machines. But microformats cover only a few types of data (addresses, friend links, location ...) because of how they work. Each of them is a specific convention that must be agreed upon. Used without care, they can also mix poorly.

RDFa is an attempt to obtain both the flexibility of RDF and the simplicity of microformats. Microdata was the answer to RDFa, but with a different data model (roughly arrays and hashes, not a relational model). Unlike microformats, they do not dictate what information is provided, but how exactly it is encoded.

To complete what we are missing, we now have schema.org, which is an initiative of large search engines (Google, Bing, Yahoo, Yandex) to index web data. schema.org coordinates these values, so the search engine knows that, say, events have locations. Microdata was originally used by schema.org, but now both microdata and RDFa are supported.

These days, I would ignore microformats and go to schema.org. My personal taste is RDFa encoding, but either it or the microdata should work fine.

Answer 2

all three are attempts to make web content more meaningful.

rdfa encountered many barriers to entry; he shared the same growing pain that xml (xml-based rdfa) did in his early years on the Internet, but was probably more significant because there were fewer developers to process.

I do not know enough about rdfa to recommend it for microdata. I'm prone to microdata because Google, Yahoo !, and Microsoft (now Bing) came together and created it. Currently, rdfa is being developed and a proposal for microformats is being made. in addition, microformats were already in mass production and consumption on the Internet. so the big 3 decided to conspire and came up with microdata. I'm a little exhausted, I think, because I don’t fundamentally understand why microformats were discarded. sounds like a bunch of smoke and mirrors.

therefore I recommend microformats for everyone. they are just simple. and so amazing. what can you achieve with microdata that you cannot with microformats?

who said .... I would choose microdata via rdfa because they are just as light. and data attributes are far superior to html classes. in fact, maybe a big bonus? attribute data? just like your little research, I already looked at long and hard discussions about microdata, but all I can find is normal, template messages.

Answer 3

I suggest ignoring the semantic network altogether. Because of this, search engines will not send you more visitors. Instead, they will use perfectly organized data to provide an answer without sending you visitors at all.

Today you can see the problem with the following movie example: https://www.google.com/search?q=The+Godfather

Displays IMDb and Rotten Tomatoes ratings. Fragment of Wikipedia. Nice for users, bad for these sites. Or how often have you visited IMDb in the past and today?

And do not forget. The displayed data is not from IMDb or Rotten Tomatoes. Dates, director, awards, music, images, etc. Were collected from other sites. For example, a search engine can easily search in its database "The Godfather" + "Director", and if 99 of the 100 sites include the name "Francis Ford Coppola", it is easy to check the answer without any manual interaction.

Finally, search engines can create their own content without paying or mentioning the authors. And with semantic classification it will be easier for you.