[avr-gcc-list] ok, so this message *is* off-topic

[rusty+avr-gcc-list]

I'm a programmer who's getting his feet wet with microcontroller
hardware and programming.  I don't understand all this stuff about
jtag, ice, isp, etc.  When I see remarks on the Atmel page about how a
"programmer isn't needed" my reaction is "I'm not needed?" but
obviously they're talking about something else.

I've been looking at the AVR book by Dhananjay Gadre which I'll
eventually probably buy but as basic as that book is even he assumes
more knowledge about this stuff than I have.

Is there a web page or something that explains this stuff?  Ideally in
a generic way not specific to any microcontroller, and with specific
examples for various popular microcontrollers.

(For example, I'm ordering an AVR Butterfly but have no idea what to
do to be able to download code to it.)