EVE PLEX can be traded or sold between players on the in game market. It can also be used in the New Eden Store to upgrade your account to get Omega Clone state, purchase virtual goods, and activate other account services.
1100 PLEX is valued at $0.0363 Cents each. This is the most popular package. This is the best value if you wish to keep your real world costs lower when selling the PLEX for ISK. This is enough to set your clone at Omega for 60 days and have 100 left over.
To use PLEX in the New Eden Store, It must be placed in your PLEX Vault. The Vault is a secure location in your inventory, shared across all characters on your account, where it can be placed for use in the New Eden Store. You can find the Vault in your inventory in the Neocom (Upper left corner of your game screen).