APPINT

Enable - disable Object Snap on extended intersection 

CEN

Enable - disable Object Snap on center

ENDP

Enable - disable Object Snap on end points

EXTE

Enable - disable Object Snap on extension 

INT

Enable - disable Object Snap on intersection

MID

Enable - disable Object Snap on mid point

NEA

Enable - disable Object Snap on nearest point

NON

Disable all Object Snaps

QUA

Enable - disable Object Snap on circle, arc, ellipse and elliptical arcs quadrants

PAR

Enable - disable parallel Object Snap 

PER

Enable - disable perpendicular Object Snap

SNAPS

Go to the Snaps management dialog

TAN

Enable - disable tangent Object Snap

VER

Enable - disable Object Snap on vertices