A wallet manages a user's private keys. Wallet software is used to send and receive Bitcoin. It also keeps track of the user's transactions, addresses, and balance.
This tag should be used for questions pertaining to Bitcoin wallet software. Wallet software handle users' keypairs, addresses, and transactions as well as allowing for the sending and receiving of Bitcoin.
This tag can also be used for wallet files (the files containing the wallet's information), their contents, formatting and any other related topics.
This tag should not be used for any questions relating to the traditional definition of the word, such as "Where can I buy a wallet with bitcoins?"