Marquee tool 2 : selection method

Path:	Photoshop Lecture > tool > Marquee tool
Summery:	selection method of  Marquee tool
Level:	★★
Connection:	Marquee tool 1 : shapes,  Marquee tool 3 : feather,   Marquee tool 4 : style

1) New Selection : always selected area as the final. default of Marquee tool.

2) Add to Selection : selected Marquee + Shift

   draw the first shape then draw the second shape.

   shapes is added. and check the cursor. 

3) Subtract from Selection : selected Marquee + Alt
    same method with '2)'. 
    subtract the common area of the shapes. check the cursor, too.

4) Intersect with Selection : selected Marquee + Shift + Alt
    same method with '2)'. 
    remain common area of the shapes. check the cursor, too.