Short answers, pulled from the story.
Frigg is a goddess of the Æsir, the principal family of Norse gods, associated with marriage, prophecy, clairvoyance, and motherhood. Nearly all surviving sources name her as the wife of Odin, and she dwells in the wetland halls of Fensalir. Her children with Odin include the god Baldr.
Friday comes from the Old English Frīġedæġ, meaning "day of Frig," which traces back to the Late Proto-Germanic phrase for "Day of Frijjō." This was a translation of the Latin Veneris dies, the day of Venus, substituting the Germanic goddess's name for the Roman one in a practice known as interpretatio germanica.
Baldr began having dreams warning of danger to his life, so Frigg extracted protective oaths from elements, forces, diseases, animals, and stones. She omitted only a young mistletoe shoot growing west of Val-hall. Loki, disguised as a woman, learned of this exception and tricked Baldr's blind brother Höðr into shooting Baldr with mistletoe, killing him. Frigg then asked the Æsir who would ride to Hel to seek Baldr's return; Hermóðr accepted, but the rescue failed.
The Second Merseburg Incantation is a healing spell preserved in a 10th-century manuscript found in Merseburg, Germany. It calls upon Frija (Frigg) and her sister Volla to heal a horse's wrenched foot, alongside other gods including Woden. The spell places Frigg in a chain of divine healers and documents her continental Germanic role well before the 13th-century Norse compilations.
Scholars debate whether Frigg and Freyja descend from a single Proto-Germanic deity. Scholar Stephan Grundy describes the question as "difficult" due to the scarcity of pre-Viking Age sources. A key distinction is that Frigg's name is attested across the entire Germanic world and reconstructed as Proto-Germanic *Frijjō, while Freyja's name appears only in Scandinavian sources.
According to the 7th-century Origo Gentis Langobardorum, when the Vandals demanded tribute from the Winnili and asked the god Godan for victory, the Winnili leaders called upon Frea (Frigg). She counseled the Winnili women to arrange their hair around their faces like beards, then turned Godan's bed to face east so he would see the Winnili first at sunrise. When Godan called them "Long-beards" (Langobards), Frigg replied that having named them, he must now give them victory, which he did.