Short answers, pulled from the story.
Titus Flavius Vespasianus was Roman emperor from 79 to 81 AD and a member of the Flavian dynasty. He was the first Roman emperor to succeed his own biological father, Vespasian. Before becoming emperor he commanded Roman forces in Judaea during the First Jewish-Roman War and is best known for destroying Jerusalem and completing the Colosseum.
Titus commanded the Roman siege of Jerusalem in 70 AD, encircling the city with four legions and cutting off food and water supplies. After breaching the city walls and capturing the Antonia Fortress, Roman forces destroyed the Second Temple and razed the city. According to Josephus, 97,000 people were captured and enslaved following the siege.
Mount Vesuvius erupted shortly after Titus became emperor in 79 AD, burying Pompeii and Herculaneum and killing thousands. In the spring of 80 AD, a fire burned large parts of Rome for three days and three nights, destroying the Pantheon of Agrippa, the Temple of Jupiter, and other major public buildings. Suetonius also records that a plague broke out during the fire.
Titus completed the Colosseum, known then as the Flavian Amphitheatre, in 80 AD. Construction had begun under his father Vespasian in 70 AD. The inaugural games lasted a hundred days and included gladiatorial combat, animal fights featuring elephants and cranes, mock naval battles, and chariot races.
Berenice was the sister of the pro-Roman King Agrippa II and a member of the Herodian dynasty. Titus began a relationship with her during the Judaean campaigns, and she returned to Rome in 75 AD to live openly with him in the palace. Roman public disapproval and denunciations by Cynics in the theatre led Titus to send her away, both before and after he became emperor.
According to ancient sources, Titus's last words were "I have made but one mistake." He died of a fever on the 13th of September 81 AD at a roadside station in the Sabine territories, reportedly in the same farmhouse where his father had died. Cassius Dio believed the remark referred to his failure to have his brother Domitian executed when Domitian was found to be plotting against him.