herkforth screenshot
Explanation:
1st line: block number and block title (first line in shadow block)
2nd line: stack (top of stack on the right)
herkforth source code (see also: herkforth colors). Cursor is in reverse video.
divider
Source code for word under cursor.
some command history
input line (white rectangle is my terminal's cursor)
This screenshot was taken after typing 100 then pressing return, then random, then pressing return, then . and pressing return. the 13 is output.