Hello, Of recent a noticed that most of the higher or very high level developer/programmer in any language or framework, always like to theme their various different IDE with black background.
could it because of their long time setting in front to a computer while reducing light intensity into their EYES?
It depends from person to person… I too mostly like the black background, but for the desktop… in the IDE I’m better with a grayish (not completely white) background
why do u have the preference other then white??
light intensity issues?? or ?? 
Interesting question. I also use black background because like you say it feels more comfortable for my eyes not to look "into the light" all the time.
I also found this:
http://www.codinghorror.com/blog/2005/07/code-colorizing-and-readability.html
It really seems to be a matter of personal preference, because unlike the comment states, i find the middle example most readable.
As I wrote it depends from person to person… I personally find black background more natural…
I’ve always felt uncomfortable with white background. This was actually more of a problem back in the CRT days. It’s still a problem if I can’t slightly reduce the brightness of the monitor. Lucky me I’m not doing graphical design 
.
For window background I settled for 192,220,192 (slight color blindness ). For command line usually black background.
White background or large blocks of white looks good for web pages but isn’t a good idea for all day use. It’s also a pity many web pages nowadays use improper color combinations. One would imagine the purpose for company web sites would be to have as many potential customers as possible being able to read the pages without difficulty.
/Tommy
Сreative persons change their background everyday.
i seems to have problems with white background(sore tears), so i decided to change to black, now i can stay 6 hours on the computer 
I’m using white background. You need enough light in the room to feel comfortable with it.