An apparatus, a method and a medium for providing and processing information, whereby users of a chat system send easily and rapidly to one another a URL for uniquely designating the location of a file on the Internet. In one embodiment, a number of wide bandwidth antennas, 2 MHz to 40 GHz, are incorporated into a body-worn vest or garment such that an individual wearing the vest is being provided with a wearable system for indicating the direction of the source of incoming signals. A computer readable storage medium encoded with computer executable instructions, which, when executed by a processor of a computer, cause the processor to: reduce image artifact caused by differences in variances in projections used to update a voxel of an image for one or more voxels of the image using an iterative statistical reconstruction algorithm.