What are each of the different files that appear when I save my experiment?

I’ve looked through the documentation but couldn’t find the answer to this, apologies if I missed it!

When I save my experiment I get the following files:


Could anyone give me a quick rundown of what these are each for?

What I’ve gathered so far from looking around online is that the .psyexp file is the main format a psychopy experiment file takes. The .js file is a conversion of that file to be run online.

But what is the legacy-browsers version for? And what about the lastrun.py file?