CyberGhost VPN anonymizes you on two different levels. The first level is the exchange of your original IP address, assigned to you by your ISP, with the IP address of the CyberGhost VPN server you are logged into. That way any data sniffer will not get your address, but the one of the respective CyberGhost VPN server. This level is of a fixed nature.
The second level is more an additional protection and depends on the amount of users, who reside on the same server as you at the same time. All current users on a certain server will surf the Internet with the same CyberGhost VPN IP address. This level is of a variable nature, because the more users a server bears, the better a single user gets hidden by the others.
The latter is also the reason, why the server map provides you with an anonymization score for each server, based on the number of users online. If a server is highly frequented, your anonymity is better than on a server with less users. Then again, the traffic speed might be slower than on a server with less users. Vice versa a low anonymization score reminds you, that less users are surfing at the same time - but they might do it faster ;-).