$.each object

HTML

<ul id="log"></ul>

JavaScript

var officers = {
    captain: {name: "Jean-luc Picard", rank: "Captain", race: "Human"},
    first_officer: {name: "William Riker", rank: "Commander", race: "Human"},
    operations_officer: {name: "Data", rank: "Lt. Commander", race: "Soong android"},
    medical_officer: {name: "Beverly Crusher", rank: "Commander", race: "Human"},
    tactical_officer: {name: "Worf", rank: "Lietenant", race: "Klingon"},
    chief_engineer: {name: "Geordi La Forge", rank: "Lt Commander", race: "Human"},
    counselor: {name: "Deanna Troi", rank: "Commander", race: "Half-Betazed"}
};

$.each(officers, function(position) {
    $("#log").append($("<li>").text(
        this.name + " is a " + this.race + " who serves as " +
        position.replace(/_/, ' ') + " aboard the USS Enterprise NCC-1701-D."
    ));
});