D3 3.x, HTML, CSS, JavaScript
draw path on mousedown
http://bl.ocks.org/mbostock/3680999
draw a single line update 1 - now draggable
draw a circle on mousedown
draggable and resizable on right edge
No-Library (pure JS), HTML, CSS, JavaScript
jQuery 2.1.0, HTML, CSS, JavaScript
jQuery 1.7.2, HTML, CSS, JavaScript
once a line is drawn, click on either ends point to resize/reposition
user draws a rectangle and is able to move it around
click a button to draw a certain type of shape