Is tnt an improvised explosive device?

Answer 1

TNT is an explosive compound, and can be a component of an I.E.D., but is not one in and of itself, anymore than any other explosive by itself is an I.E.D.

The name I.E.D. pretty much defines what it is: it's a device - that is, some assembly of parts - which is manufactured in an ad-hoc, improvised, and non-formally manufactured form, which contains some explosive.

Most common I.E.D. use the explosive filler from scavenged artillery shells (which is typically closer to RDX, the primary component of plastic explosive) as their explosive component. Custom-made gunpowder is also common, though less effective and harder to handle. Plastic explosive itself bought on the black market is also becoming more common in I.E.D.s

(as of 2010 in Iraq and Afghanistan)