Principles: the magnetic fields of current loops are given by the right-hand-rule: fingers in sense of the current, thumb in the direction of the field. Note that current loops can be thought if as having a north and south end - just like permanent magnets. A tiny compass can be used to indicate the direction of magnetic field lines at any point.
In the first two applets below, you can double-click anywhere in the applet window, and a magnetic field line will be drawn at that location. The field line will only have a direction arrow at the point where you click. Also, it may leave the applet window only to re-enter somewhere else. Thus you may want to click in a variety of locations to understand the field directions. "Click up" some magnetic field lines, and answer the associated question.
In the coil above (shown in cross section), which wire end (top or bottom) does the current flow out of? top end. bottom end.
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