January 22, 2020
Google uses structured data to understand the content on the page. You can help us by providing specific information about your site, which can help your site display in richer features in search results. Structured data is a standardized format for providing information about a page and classifying the page content; for example, on a recipe page, what are the ingredients, the cooking time and temperature, the calories, and so on.
Structured data schemas such as schema.org and data-vocabulary.org are very popular and Google now decided to focus only on schema.org and discontinue support for data-vocabulary.org from April 6, 2020 from google search results.
Search Console will issue warnings for pages using the data-vocabulary.org schema so that they can update the markup with schema.org markup.
If you want to be eligible for Google rich result features Google recommends converting your data-vocabulary.org structured data to schema.org.
For understanding how Structured Data works learn from here
by : Fahim Akhtar
Quick Summary:
If you want your web pages to be eligible for Google rich result features Google recommends converting your data-vocabulary.org structured data to schema.org. The support goes off on April 6, 2020.