Either simply go to http://www.fas.harvard.edu/computing/download or go to the Harvard Math Dept website (http://www.math.harvard.edu) and next to the line marked "Local" find the drop down box with "Harvard Main" on it, and find "FAS software download." Either way you should be redirected to the website http://www.fas.harvard.edu/cgi-bin/software/download.pl (note - you might need to enter your Harvard ID number and PIN to access this website, depending on what computer you’re using to download the Mathematica file to and where you're accessing this website from).

Next scroll down to the Mathematica link on the list of downloadable software (feel free to download some other useful software as well while you’re here!) Write down, or memorize, the Harvard license number L2482-2405 (you’ll need this later when you send an email to Mathematica to get a password for your copy of Mathematica).

Accept the consequences in the dialog box, and then click on "begin download" in the next dialog box if the download didn’t start automatically. Choose "save" for the download file "Mathematica.exe" and put it anywhere you’d like on your computer (this is the compressed Mathematica file – you’ll need to know where you put this file so that you can run it later on).

After the download is complete, find the Mathematica.exe file that was downloaded onto your computer and doubleclick on the file name (or run it) to extract the actual Mathematica program. This process will take several minutes and give you a couple of options (such as where to locate the file and whether you’d like the full or minimal version (I’ve just used the minimal version as the file is really large (like 400-500 MB) (please excuse the gratuitous use of parentheses here!)))

Note if things get messed up during the download - try again (reboot your machine, go have a cup of coffee, smack the computer monitor, whatever it takes). There are occasions when something just gets hung up during the download and you need to try it all over again (I had to download the same file several times to get it to work out).

Finally, you’re almost ready to play the waiting game to get a password. When the Mathematica program is loaded up and ready to go, go ahead and double click on it (it should have added an icon to your desktop for the program, if not, you need to find where the Mathematica installer program located the Mathematica program on your computer – sometimes it’s located under a subfolder named "Wolfram Research" as this is the company that makes Mathematica).

Now it gets a bit confusing – after you start the Mathematica program it will immediately ask you to "personalize Mathematica" (and no, this doesn’t mean to accessorize your copy – it’s getting you to provide a password, which you don’t have yet!) Type in your name, and for organization just type Harvard University, and then the license number (which you’ve memorized by now just for such occasions!) L2482-2405. Keep the toggle button switched to "Single Machine" (that’s what it should have defaulted to). Now click okay and it should ask you for a password that you don’t have yet...

Two options – click on the "Web" button right next to the password box and follow those instructions, or go the website http://register.wolfram.com later on your own to register your copy of Mathematica. In any case, copy or write down the "MathID" number exactly as it appears in the box above the blank password box (you’ll need it in a few minutes).

In either case you’ll be directed to a Wolfram Research website, and after having to type in your license number if you went to the http://register.wolfram.com site on your own, then you will be asked to choose one of two possibilities. Choose "I want to register a product and generate a password." and click on "continue." At the next screen make sure the version is 5.0 and enter the MathID number on the first line of the box below, and then type in anything in the Machine Name box next to it (I typed "Andy’s Home Computer," for instance).

Click "continue" and enter even more info! For "organization" – Harvard University, "department" – Math, and "lab or facility" I just left it blank (you could put in Math 21a here). The email address is crucial as that’s where you’ll receive your password when it comes. Then hit "continue" and you should be done for now – you can shut down the internet site and take a break. You can close down the half-started Mathematica program by clicking on "back" and then "quit" as it will probably be quite a bit of time before you can actually start using it.

And now the waiting game... your request for a password might take up to a day or two to come back to you depending on how swamped they are with requests right now, so be sure to do this whole downloading/password request thing early on so you don’t get messed up by this timing!

Once the email comes back to you with the password information, just go back to the Mathematica program and restart it follow along until you get to the password dialog box again, and enter your personal password to start up Mathematica.

Wow, you should be done for now – now it’s just a matter of figuring out how to use Mathematica – no small task for those of you how haven’t tried it before, but fortunately we have some tutorial labs to get you in shape!

To see if you've really got a working copy of Mathematica, try doing the following just to check out one neat aspect of Mathematica. Unlike your calculators that have a very limited ability for precision of numbers, Mathematica has so-called "infinite precision" which means it can keep track of numbers that have hundreds or thousands (or more) digits in their decimal expansions.

If you type "N[Pi, 100]" in Mathematica, for instance (note you have to type it exactly in this way, with the square brackets and upper and lower case choices) and then hit the shift and enter keys at the same time (this is how Mathematica knows to act on your command), then you should see Pi to 100 decimals of accuracy. Try N[Pi, 1000] or N[Pi, 10000] just for fun. Next compare the answer to 3 raised to the 100^th power on Mathematica as compared with the answer your calculator gives. Type in "3^100" on a new line in Mathematica and press shift-enter and see what you get! Pretty cool, isn't it? Wait until we get to the graphing capabilities! (If you're dying to get going with this, try "Plot[Sin[x], {x, 0, 4 Pi}]" and hit shift-enter).

Now, you probably can't wait to get started on the first Mathematica lab assignment - don't worry, we'll be doing that very soon!