Players are the backbone of every club. Your success in matches and competitions will depend on the quality of your players, just as in real life.
When you take control of a club, you will be given a few players in your team to start with. You can have a look at those players in detail, and decide which ones you need to keep, and which ones to get rid of, based on your plans and playing strategy. The overview of current players are available at the Players link under the Squad menu.
Just like your club, other teams will have their own players. You can view the list of players currently at a club in the team's information page, which can be accessed through the link to that team in various pages on the website.
You always need to have a minimum of 18 players in your squad at all times. You cannot sell or release a player if it will take your squad size below this limit. Similarly the maximum squad size allowed is 30, beyond which you will not be able to recruit further.
Rating is an indication of how good a player is. It is determined by his individual attributes and the position he plays in. Rating can vary from 10 to 100, 10 being the worst and 100 the best. However do not judge a player just by looking at his rating. His actual performance during matches will depend upon a lot of other factors which are explained further.
Your club can recruit players from other clubs or from your own Youth Academy. You can either buy a player listed in the transfer market by another club, or get him on loan for a season. Details about loans and transfers are covered in the Transfers section, and promoting players from the Youth Academy in the Facilites section.
Some players may not be playing in any clubs at the moment. Such players can be added to your squad by offering them a contract, please see how to acquire teamless players in the Transfers section of the tutorial.