A conference is a meeting of people who “confer” about a topic.
The publication rate of presented abstracts is considered a proxy marker of the scientific strength of a conference.
The advantages of online conferencing are multiple. It removes the need for long and expensive travels that take up a lot of time, and remove you from your family and practice. By avoiding cost for travel and stay, conferences (and therefore, knowledge) can be made accessible for a larger audience, especially in developing countries. By avoiding travel itself, assuming you do not travel by bike or sail boat, CO2 emission can be reduced too. Online conferencing also allows for a more flexible schedule: you may not be able to attend a conference abroad for that one surgery or appointment that cannot be postponed. In that case you may still be able to attend other lectures or sessions if you can follow them from your office or your home. It is perfectly possible to include checks whether you actually watched a video, which would allow for CME points as you would get during an on-site conference 1).