Its a javascript graphing library. We've started using it at work a bit for our online dynamic graphs. Its a graphic grammar on top of the d3 js library.

We seem to prefer the lite version, which is simplier.

If you look at the examples, you can click a button a go to a dynamic editor which we rather like.[1]

https://vega.github.io/vega-lite/

If JS and web browsers aren't your thing, they have python version called "altair"

https://altair-viz.github.io

[1]https://vega.github.io/editor/#/examples/vega-lite/stacked_b...

My guess is this, since we are talking about tableau: https://vega.github.io/vega/

Thanks. Seems extremely similar to Plotly upon first glance and their viz data structures.

Vega is nice for its declarative, portable nature. Also, it makes certain things very easy such as embedding interactive Vega charts and generating images of charts without needing something like PhantomJS.