A name service maps a readable name to an address, and can also point to other records. Wallets resolve the name at send time, which greatly reduces the risk of pasting a wrong or poisoned address.
Two cautions. Names are usually rented, not owned forever: if a registration lapses, someone else can take it and receive funds people still send there. And names are easy to imitate with alternative characters or near-identical spellings.
Example: renewing a name costs a few dollars a year. Forgetting a renewal on a name your counterparties have saved is how funds end up in a stranger's wallet with no recourse whatsoever.
Related: crypto-address, address-poisoning, block-explorer, smart-contract-wallet