I am in a biological field (medicine) but I have genuine passion for mathematics. I want to learn it on my own , in my spare time. Mathematics , as I gather, is learned best when you have grasped the prerequisite concepts for the area you are currently interested in. Kindly suggest a sequence of study for the following areas ...
1) Algebra
2) Calculus
3) Discrete math
4) Geometry
5) Probability and statistics
6) Mathematics Software Packages (which one do you suggest for primarily educational, nonprofessional use)
6) Any other areas of fundamental importance that I may have missed
EDIT: does first order logic and set theory belong up there ?
I'm unclear what you mean by "Algebra"; if you mean stuff like working with polynomials, basic equations, symbolic manipulation, etc., then that goes first. If you mean "abstract algebra", then you can wait.
Added. Likewise: if by "geometry" you mean classical geometry, or even projective geometry, then the following applies.
Calculus, Discrete Mathematics, and Geometry, are independent enough that their order doesn't matter.
Added. However, if by "geometry" you mean analytic geometry, then it should definitely precede calculus, and the same is true if it means trigonometry. I think it unlikely that you meant "differential geometry" or "algebraic geometry", but if you did those are very advanced topics that should wait until well after calculus, abstract algebra, and real/complex analysis.
For introductory probability and statistics you'll find Discrete Mathematics very useful; for more advanced probability and statistics, Calculus is a must.
An "introduction to proofs", which would include some set theory, some basic logic, etc., can be done at the same time as Discrete Mathematics, or immediately after.
After all this, then you can hit linear algebra, abstract algebra, real or complex analysis, in pretty much any order (though complex analysis should follow real). Abstract algebra is a bit easier if you've taken linear algebra, but this is not strictly necessary.
If you happen to find probability and statistics very interesting, then you should do some measure theory after the real analysis.