file:///sdcard/ is the access address for the SD card, then what is the address for internal storage on my HTC?
You probably won't be able to access much of your internal storage via the web browser. The URL you mentioned,
file:///sdcard/, consists of two parts: the protocol (
file://), and the path (
/sdcard/). So basically, you just have to change the path accordingly. You can check with a file manager what the path to the desired destination is.