Inside a ZIP file, front to backoffset 0 ──→ end
Local file entries
one per file: a small header, then the data
Central directory
the index: every file's name, size, and offset
EOCD
the very end
A ZIP is read from the end. Hover the three parts, or trace the read order, to see why.
The index sits at the end, so a reader opens a ZIP back to front.