A Draft Pool is when a group of people get together (either Online or Offline) and take turns drafting NHL players to build unique teams.
A player can only belong to one poolie at a time, therefore the better the player - the higher the draft pick. For example, Connor McDavid probably will be picked with one of the first picks in the pool.
Draft Pools are ideal for groups in the range of 2 to 20 poolies. Participants hockey knowledge tends to range from Average to Expert. However, no matter the level of expertise - there are plenty of draft tools (pre-season rankings, magazines, etc) out there that can give any poolie an edge.