There's (still) so much that we're just guessing at, RNA World, etc, segregation of reactive environments in lipid bubbles...

One interesting thing I keep coming back to, before information transfer, whether through RNA or DNA, is ATP, ATP, ATP...

If you're not a Biologist, ATP means Adenosine Tri-Phosphate - and that's the little energy machine that runs everything. Adenosine is one of the 4 bases that, perhaps further down the line, got co-opted for information storage.