Goaltender1 of 5
The goalie is the player most responsible for preventing the puck from entering their team's net. As a result, this position is one of the toughest to play in all of sports from both a physical and mental aspect.
Physically, goalies are required to wear special equipment that is designed to protect the body from the direct impact that a really hard, really fast hockey puck could cause. Mentally, an immense amount of pressure is placed on a goalie to perform. If a goalie plays well, their team's confidence could grow and could result in a win. If a goalie lets in a series of soft goals and plays poorly, their team could become significantly deflated and lose. As a result, the position requires mental strength and an ability to move on quickly from both good and bad moments during a game.
Defenseman2 of 5
If a team is operating at full strength during regulation play, they play with two defensemen on each shift. A defenseman's primary responsibility is to prevent the opposing team from scoring. However, there are multiple ways to do that, and that is reflected in the differing styles that are seen in defensemen.
There are creative, offensive-minded defensemen that like to handle the puck and lead their team up the ice. These players are often smaller, quicker and less physical. On the other end of the spectrum, there are defensemen who are more defensive-minded and tend to stay close to home (their own net). These players are often bigger and more physical.
There are also those rare examples of players that demonstrate a combination of each skill set. While it may be difficult to find that rarity, coaches will often look to find a balance between offensive-minded and defensive-minded defensemen within each defensive pairing.
Center3 of 5
Much like a quarterback in football, a center is often expected to lead the team at both ends of the ice. While players in this position often have flexibility when it comes to their positioning and on-ice coverage, the center primarily stays toward the middle of the ice and away from the side boards. Due to that fact, centers are ideally stronger, faster skaters that can cover more ground through the defensive, neutral and offensive zones.
From a skill standpoint, centers are often expected to be creative passers looking to put their teammates in advantageous situations. Centers are also asked to take face-offs for their team. Taking all of this (leadership, intelligence, unselfishness, physical ability) into account, coaches understandably place a high value on this position.
Left Wing/Right Wing4 of 5
As the name indicates, the wingers line up on either side of the center and generally play on their designated (right or left) side of the ice. Certain players tend to bring varying skill sets to the table as a winger.
There are some wingers who serve as out-and-out goal scorers. They play off of the creativity of their teammates and focus primarily on converting scoring opportunities. There are other wingers who operate as physical checkers who hit and disrupt opponents. There are "power forwards" who tend to combine those two methodologies. Setting aside individual styles, all wingers are expected to demonstrate a willingness to work in the corners and along the boards within all three zones.