Answer:
Joe Biden's presidential inauguration ceremony took place on January 20, 2021. President Donald Trump, who ended his term, did not attend the inauguration motivated by allegations of fraud against Biden and his clear antagonism with the president-elect, in addition of the political tension generated after the elections around this issue (especially after the assault on the Capitol, which led to the deployment of 25,000 soldiers to prevent any conflict during the event). In addition, in relation to the coronavirus pandemic, mass events were canceled, whereby only 1000 people were able to attend the event, while in the past, up to 200,000 people could attend the inauguration, which made the inauguration of Biden has been one of the least crowded in history.