I have a somewhat unusual question. I do not know what software are created these images http://www.keil.com/pack/doc/mw/FileSystem/html/index.html
You mean the block diagram: http://www.keil.com/pack/doc/mw/FileSystem/html/filesystem.png ?
Yes.
I wouldn't call them "graphs".
Just about any business drawing software should be able to do that.