Metamaterial Technology - Transmission line based applications - Antenna applications - Cloaking  Metamaterial cloaking involves research with a relatively new class of artificial composite materials to develop possible future invisibility or cloaking device applications. Other technologies derived from this research are also included in this article. The new artificial materials, first physically realized in the middle of the year 2000, are metamaterials - discussed briefly in the first section.  This is followed by a discussion of what it means to "cloak" something, or render it invisible; and answer why it's a challenge. After which theoretical approaches introduce the subject, framed in explaining why metamaterials are part of these cloaking approaches.  These studies are based on the scientific method, and published in peer-reviewed, scientific journals. The methods employed and the published results are often distinct from popular media accounts. For the popular-media views see the other articles related to this topic. Cloaking using SRR(J. B. Pendry et. al "Metamaterial Electromagnetic Cloak at Microwave Frequencies", Science express, 2006 [10]) 2D Cloaking using chip inductors and chip capacitors(left) and simulation results(right)