Who was the replacement singer for ACDC?

Could you please clarify who took over as the lead singer for AC/DC after their previous frontman's departure? I'm curious to know the identity of this new vocalist who has filled the shoes of such an iconic figure in the rock music scene. I'm assuming there must have been a significant amount of buzz and anticipation surrounding the announcement of their new singer, so I'm eager to learn more about their background and what they bring to the band.