How to pass parameters between forms in HTML?

I have a 2-step registration process which consists of 2 different HTML pages. The second (and final) step collects all the data and sends it to the server for evaluation. For simplicity, let's say I collect user's name in the first form and user's age in the second:

formA.html:

<form action="formb.html" method="get">
      Name: <input id="age" type="text" name="age">
      <input id="submit_button" type="submit" value="CONTINUE">
</form>

formB.html:

<form action="serverscript.py" method="post">
      Age: <input id="name" type="text" name="name">
      <input id="submit_button" type="submit" value="SUBMIT">
</form>

How can I "propagate" the "name" that user has entered in formA.html to formB.html so that I can send name,age to the server?