Since the launch of the sitemap format in 2005, we used to have a sitemap by content type. Mobile content, Video, Image, News… Everyone had their own file. Google, Bing, Yahoo and the other engines had agreed on a common protocol. Today Google stands out by offering webmasters to group all of their content in one file …
With the arrival of the universal research and the multiplicity of content growth, it has become difficult to manage the different Sitemaps. Even if in most cases the management of these files is done automatically, simplification is welcome.

From now on, you can therefore use a single file to submit your content to Google. The structure of this new sitemap remains the same as that of a standard sitemap, you will therefore find your habits in the matter.
Here is an example of a sitemap containing different types of content:
http://www.example.com/foo.html http://example.com/image.jpg http://www.example.com/videoABC.flv Grilling tofu for summer
Note that Google does not refer to news content, for the moment for the latter a specific format therefore seems to be maintained.
There is still a question about the arrival of this new format. By offering this possibility, Google differs from other search engines and departs from the agreements that had been reached with them via thealliance sitemap.org !
In my opinion, the other engines will quickly follow the trend launched by Google, do they have a choice anyway?
Source: Google