MODIFIER KEYS for LINE TOOLS

SHIFT

OPTION

COMMAND

SPACE BAR

TO USE WITH LINE TOOLS:

Line Segment Tool:
shift key - straight line
space bar - move on fly
option key - from center out

Arc Tool: (arc tool is .25 ellipse)
shift key - .25 of CIRCLE
space bar - move on fly
option key - from center out
"c" key - closes off
"f" flips
up and down arrows - changes degree of slope

Spiral Tool:

shift key = 45 angle
up and down arrows - add and reduce segments
command/ (drag) - adjusts decay 

Use the Scissor Tool to cut lines

To Join Paths - Object>Path>Join
(guides must be locked to join paths)

To Align and Join Points:
select with the Direct Selection Tool and click the Join Points icon in the Control Bar
To Average Locations
(object>paths>average[both]) or
command/shift/option/J