Checks the time at which an address was first seen on the network.
Checks current balance as received BitCoins minus sent BitCoins for an address.

Checks the total BitCoins received by an address.
Checks the total BitCoins sent by an address.

Converts a BitCoin address to the Hash160 format used internally by BitCoin.
Converts a BitCoin Hash160 (in Hex) to a valid BitCoin address.

Checks if the address is valid. Note that it is impossible to determine whether someone actually owns the address. Someone could easily get a valid address.
Generates a Hash160 from a BitCoin's public key. Public keys are either the first 65 bytes (130 hex characters) of a scriptPubKey or the last 65 bytes of a scriptSig.