The copy on the website is generally marketing heavy with things like "Coda is a new doc that grows with your ideas" but things like "Coda is a new canvas that blends tables and text together" makes sense to me, imagining that it's like a document that also have tables, that you can do computations on (so like Excel). The example videos/GIFs seems to show the functionality and when I reached the end, I feel like at least have a slight idea what it's about.
Wouldn't be enough to compare it with other services, but I definitely have "some idea" of what Coda is.
Am I alone in understanding this from looking at the website, without any prior experience?
I do know some other examples that could fit into the "Classic startup landing page design where they forget to explain what their product is to potential users/clients" ending of your comment, but I don't think Coda missed the mark on explaining what they do.