The main goal of the Daily Scrum is to inspect the progress of work in the sprint. Based on the current state, the team adjusts its work or its sprint backlog to achieve the Sprint goal.
There is a 15 minutes time-box for any team size. If the event takes longer, it should be considered an indication there is something wrong.
The Daily should take place at the same time and place every working day, as consistency removes complexity.
It is an opportunity for developers to update and synchronize their work for a given day in order to get closer to meeting the Sprint Goal.
People outside the team can attend, but should not interfere.
Among the advantages the meeting provides, are improved communication, identified impediments, quick decision-making, and the elimination of the need for other meetings with a similar purpose.