Unleavened bread Unleavened bread Unleavened bread is any of a wide variety of breads which are not prepared with raising agents such as yeast. Unleavened breads are generally flat breads; however, not all flat breads are unleavened. Unleavened breads, such as the tortilla and roti, are staple foods in Central America and South Asia, respectively. Unleavened breads have symbolic importance in Judaism and Christianity. Jews consume unleavened breads such as matzo during Passover - various traditions explain this usage. Unleavened bread also features in some Western Christian liturgies during the Eucharist, a rite derived from the Last Supper when Jesus broke bread,
H.239 H.239 H.239 is an ITU-T recommendation from the H.32x Multimedia Communications' macrofamily of standards for multimedia communications over various networks. The H.239 recommendation is titled ""Role management and additional media channels for H.3xx-series terminals"". Practical importance of this recommendation is its setting forth a way to have multiple video channels (e.g., one for conferencing, another for presentation) within a single session (call). H.239 builds on the ITU-T's H.32x (which includes H.323) and H.245 series of standards, called "recommendations" by the ITU. Tandberg introduced the ability to send a computer or video presentation along with a video teleconference session in 2000