 The recent advancements in digital coding metasurfaces have enabled simultaneous control of electromagnetic, EM, waves in both space and frequency domains. These metasurfaces use spatial and temporal modulation to manipulate incident EM waves in a transmissive or reflective fashion, resulting in time reversal asymmetry. This enables non-reciprocal EM wave transmission and reception via surface to leaky, wave transformation, and harmonic frequency generation. The digital coding of these metasurfaces also allows for non-reciprocal transmission and reception of EM waves by breaking the time reversal symmetry. This could lead to many applications, such as simultaneous transmitting and receiving, unidirectional transmission, radar sensing, and multiple input and multiple output, MIMO, beamformers. This article was authored by Shagiek Vosugetaba and Chang Tse Michael Wu.