Twitter_LED project

Since I'm interested in connecting the internet with physical objects. I want to figure out the way to on/off a LED by
a certain kind of twitter's comment. (like "on" for turn on a LED.)

This is probably easy, for others, but since I'm new to Arduino. I'll start with basic stuffs ( like serial.read()).

And this is what I've done today;
On/Off a LED, by typing a word "d".


But in this program, Arduino only reacts to one letter, not a word(a sequence of letters).
In the next step, I'll try to how to get Arduino react to a word.