first_.first(array, [n]) Alias: head, take Returns the first element of an array. Passing n will return the first n elements of the array. _.first([5, 4, 3, 2, 1]); => 5

findWhere_.findWhere(list, properties) Looks through the list and returns the first value that matches all of the key-value pairs listed in properties. If no match is found, or if list is empty, undefined will be returned. _.findWhere(publicServicePulitzers, {newsroom: "The New York Times"}); => {year: 1918, newsroom: "The New York Times", reason: "For its public service in publishing in full so many official reports, documents and speeches by European statesmen relating to the pro

findLastIndex_.findLastIndex(array, predicate, [context]) Like _.findIndex but iterates the array in reverse, returning the index closest to the end where the predicate truth test passes. var users = [{'id': 1, 'name': 'Bob', 'last': 'Brown'}, {'id': 2, 'name': 'Ted', 'last': 'White'}, {'id': 3, 'name': 'Frank', 'last': 'James'}, {'id': 4, 'name': 'Ted', 'last': 'Jones'}]; _.findLastIndex(users, { name: 'Ted' }); => 3

findKey_.findKey(object, predicate, [context]) Similar to _.findIndex but for keys in objects. Returns the key where the predicate truth test passes or undefined.

findIndex_.findIndex(array, predicate, [context]) Similar to _.indexOf, returns the first index where the predicate truth test passes; otherwise returns -1. _.findIndex([4, 6, 8, 12], isPrime); => -1 // not found _.findIndex([4, 6, 7, 12], isPrime); => 2

filter_.filter(list, predicate, [context]) Alias: select Looks through each value in the list, returning an array of all the values that pass a truth test (predicate). var evens = _.filter([1, 2, 3, 4, 5, 6], function(num){ return num % 2 == 0; }); => [2, 4, 6]

extend_.extend(destination, *sources) Copy all of the properties in the source objects over to the destination object, and return the destination object. It's in-order, so the last source will override properties of the same name in previous arguments. _.extend({name: 'moe'}, {age: 50}); => {name: 'moe', age: 50}

escape_.escape(string) Escapes a string for insertion into HTML, replacing &, <, >, ", `, and ' characters. _.escape('Curly, Larry & Moe'); => "Curly, Larry &amp; Moe"

each_.each(list, iteratee, [context]) Alias: forEach Iterates over a list of elements, yielding each in turn to an iteratee function. The iteratee is bound to the context object, if one is passed. Each invocation of iteratee is called with three arguments: (element, index, list). If list is a JavaScript object, iteratee's arguments will be (value, key, list). Returns the list for chaining. _.each([1, 2, 3], alert); => alerts each number in turn... _.each({one: 1, two: 2, three: 3}, alert

rest_.rest(array, [index]) Alias: tail, drop Returns the rest of the elements in an array. Pass an index to return the values of the array from that index onward. _.rest([5, 4, 3, 2, 1]); => [4, 3, 2, 1]