When you send Monero to someone you only need one piece of information, and that is their Monero address. A *raw* Monero address is a set of 95 characters starting with a '4'. The Monero donation address, for instance, is 888tNkZrPN6JsEgekjMnABU4TBzc2Dt29EPAvkRxbANsAnjyPbb3iQ1YBRk1UXcdRsiKc9dhwMVgN5S9cQUiyoogDavup3H.
Because those addresses are long and complex, you will often encounter an @OpenAlias address instead. For example, Monero donations can be sent to donate@getmonero.org or donate.getmonero.org.
An integrated address is an address combined with an encrypted 64-bit @payment-ID. A raw integrated address is 106 characters long.
### In-depth Information
The address is actually the concatenation, in Base58 format, of the *public*@spend-key and the *public*@view-key, prefixed with the network byte (the number 18 for Monero) and suffixed with the first four bytes of the Keccac-256 hash of the whole string (used as a checksum).