Benefits/drawbacks to different Schema markup languages (ie. JSON-LD, Microdata, RDFa)

[Brian_Dowd]

Just a question (or questions) I have wondered about. What's the difference, besides the actual encoding, between the three? Why have three? Why not just the one? Seems to me that Microdata is the easiest, but maybe I am wrong. Is there a reason to use one versus another? I have not found anything explaining this on schema.org - I suppose this is just a discussion versus getting one right or wrong answer. I am just curious of the opinions of people in the SEO MOZ community. Unless of course there is one answer. I'll take that too.

[Brian_Dowd]

Great, Peter. Thanks for the answers. I now understand the difference. Much appreciated.

[Mobilio]

That's right. JSON-LD doesn't require change of HTML compared with Microdata and RDFa. And this is one of answers why JSON-LD is beautiful. Second is because you can make changes in JSON-LD without touching HTML. Like adding new fields, parameters, etc.

About placing. I think that this can be just on home page. Placing in each page is pure rich snippet spam.

[Brian_Dowd]

Hi Peter,

Thanks for the answer. So, as I understand it, and keep in mind this is coming from someone that is not very code-savvy, with JSON-LD, one could put the script anywhere in the HTML, the header, the body, the footer, etc. and it won't show up on the actual page, but the search engine will be able to read it. This implies that no changing or tweaking of the actual HTML is necessary, no messing around with 's or

's like you would with Microdata or RDFa, correct?

A follow up question, if I may, how would you implement something like a "local business" schema with JSON, would you put the script on every page, in the footer perhaps? Or would you just put it on the home page? Does it matter?

Thanks

[Mobilio]

So far we have Microdata, RDFa and JSON-LD.

I'll cover Microdata and RDFa in same because they're similar. So they both are addition to HTML attributes indicating what Schema.org field names correspond with what user-visible text on the page. Works perfect but need lot of developer work and designer changes. Because both backend (admin interface) and frontend (HTML) must be changed. And there are many issues that can be messed - incorrect implementation, "rich snippet spam", software bugs, etc. Look easy as 1-2-3 but in reality it's pain (PIA) for implementation and support. Example - only product implementation require in backend least 10 edit boxes if they're manual filled.

JSON-LD - it's relative new protocol based on Schema.org. The main benefit is that you split representation layer (HTML) from semantic layer (JSON-LD). In prev. formats - they're same and linked each other. Now they're split. This give you much more freedom than before. You can place HTML data whatever you wish and just add hidden JSON in head or in content that will add semantic marking. This is future (for now).

If you wish to read more about creation of JSON-LD then this article is for you:
http://manu.sporny.org/2014/json-ld-origins-2/