You can't make PHP remember anything, each request is separate, and disappears once it's been served. You'll have to save it somewhere (eg. text file or database), as plain text or
serialized.
You should give each visitor an ID number, and put that in a hidden form field, and use that when saving and loading the data already entered, else you will have different visitors' data all being mushed together.
I think that
file-get-contents and
file-get-contents might be sueful for saving/loading a text file, but there might be a better alternative for this situation (that I don't know).
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