What is the Lagna?
In Sanskrit, Lagna literally means "the point of contact or attachment." At the exact second an infant enters physical reality, one of the 12 zodiac signs is rising on the eastern horizon at that specific latitude and longitude. That rising sign becomes the First House of the chart.
While the Moon sign governs the interior mindscape and the Sun sign represents the core soul vitality, the Lagna represents your physical manifestation: your body, temperament, vitality, and external destiny.