While you don’t need an address book these days, we recommend you own one. Have you ever kept a date from six months ago’s number in your phone, only to accidentally purse-dial him? It’s awkward. Yes, you could simply erase him from your contacts, but you don’t always want to delete a person from your life with no way to get in touch with them down the line. Instead, jot down contact info and notes on former lovers in a classic — or cheeky — little black book.