Wordpress is a CMS masked like a blogging - platform.
It is highly flexible, highly powerful and highly extendable.
It is running on PHO + MySQL.
If you never have used any CMS before - I suggest you do the following :
Start to play !
(if you need documentation - look here and in your best new friend : the CODEX here
After you will do that - many things will start to be much more clear .
you can then start to extend it with themes and plugins .
Now - About the word "development" -
It really depends if by "development" you mean creating sites with wordpress , or creating the TOOLS for wordpress to create sites.
By tools I mean Developing themes and plugins (mentioned before )
This will come fast after that - but first , trust me - just start to play in order to understand the terminology and the process .
To make a simple website with wordpress - you actually do not need to be a programmer, just like the fact that my mom does not need to be a software engineer in order to use wordpad.
everything is with an intuitive user interface , and in the past it took me 20 minutes to teach computer - illiterate clients how to use it.
One of the greatest things about wordpress (and one of the biggest secrets for it´s meteoric growing and success ) is the wonderful and HUGE support base in form of the community , blogs, websites etc. etc..
Now - to really answer your direct question -
The opinions as to what is the "Über" dev environment for wordpress will be as numerous as the developers themselves, each has it´s own preferences and tools.
I can only recommend mine (which is also pretty common , but most importantly , EASY and SIMPLE)
If you are on PC (like you said) -
- Download XAMPP - it is a one click installation of PHP + MySQL .
it even has a built in FTP server. it can even be portable (!!)
I have been using XAMPP for wordpress development for more 6 years now , and it has never failed me . configuration works out-of-the-box.
(MAC equivalent is WAMP or MAMP - but since I never had a MAC , and hopefully never will - I can not testify..)
Some other tools :
BONUS :
- I do not use an IDE - but for wordpress I highly reccomand
NOTEPAD++ This is because when you start with wordpress, you
will need to handle CSS, jQuery, Javascript and of course PHP .and
NOTEPAD is actually the best to handle all together. Actually, with
the PLUGINS - Notepad++ can integrate all of the above together (yes,
PHP execution, DB connection, FTP, SVN integration etc, etc..)
On a personal note I must say that i owe all my programming skills to wordpress. when I started - wordpress was in it´s dipers, and I had ZERO programming skills.
Now wordpress is huge , and even if i still regard myself as a novice - have already made a dedicated industrial scale system for hotels managements integration - all based on wordpress.
this last part is not to hail my own skills, but what I said in the begining:
wordpress is highly flexible, highly powerful and highly extendable.
that´s all you need to know .
Now go and play !