1: The 2.55, by Chanel

First released in February 1955 (thus its name), the very popular 2.55 currently risks being a tad too ubiquitous. However, the slender shoulder bag created by Coco Chanel stands an excellent chance of remaining a beloved classic, not least because the legendary designer's personality remains such a large part of its allure.

Its quilted pattern was inspired by jockey coats (Chanel loved horses and riding) and the chain link straps came about because she wanted to create a bag that would leave a woman's hands free - just one of several ways she brought fashion for women into a less restrictive era.

2: The Kelly, by Hermes

The Kelly bag was created in 1892 as a large saddle carrier, but got its name only in 1956, when former Hollywood star and then-Princess of Monaco Grace Kelly used the bag to shield her pregnant stomach from paparazzi.

Both the Kelly and Birkin are wholly handcrafted by a single artisan and embellished with a discreet padlock, keys and hardware. Both can also be customised.

The differences are subtle: The Birkin has two handles and is open at the top, while the Kelly has one handle and is closed at the top. A Kelly bag takes an average of 18 hours to produce, while five Birkins are made weekly.

3: The Birkin, by Hermes

Victoria Beckham reportedly has a whole arsenal of Birkins. Marc Jacobs is so attached to his that he even takes it to the beach. Tales of the long waiting list you need to get on to lay your hands on one are legion. In short, this is possibly the most hyped bag ever.

The Birkin was born in 1984, when British model Jane Birkin sat next to Hermes chief executive Jean-Louis Dumas during a flight and told him she could not find a roomy, stylish bag. He promptly tweaked the brand's existing Kelly bag and named it the Birkin.

4: The Paddington, by Chloe

This bag was created by designer Phoebe Philo in 2005 and is easily identified because of the big - and functioning - padlock that comes with it. The lock may look a little laughable now but was responsible for kicking off the hardware trend that was all the rage in the bag universe for a while.

5: The Motorcycle Le Dix, by Balenciaga

The launch in 2001 of this biker-inspired bag is one of Balenciaga designer Nicholas Ghesquiere's biggest coups. Made of distressed goatskin and lambskin and festooned with tassles, zips and hardware, the Motorcycle remains one of the coolest remnants of the It bag era.

6: The Stam, by Marc Jacobs

Designer Marc Jacobs named this bag after his close friend, model Jessica Stam, who reportedly wanted a big bag to hold her portfolio. Launched in 2006, the purse displays Jacobs' trademark cheekiness in the way it embraces several It bag trends, including a kisslock clasp and a chain.

7: The Baguette, by Fendi

Launched in 1998, this petite purse first found fame on TV series Sex And The City, where various versions hung on the arm of leading lady Sarah Jessica Parker. Its name riffs on how it can be tucked neatly under one's arm like a loaf of the French bread and it has remained one of the Italian house's most enduring signature accessories.

8: The Spy, by Fendi

Designed by Fendi creative director Karl Lagerfeld and launched in 2005, this bag is known for its slouchy silhouette and braided handles. Its name is a tongue-in-cheek reference to the many secret compartments built into it, including a signature hidden coin purse.

9: The Muse, by Yves Saint Laurent

Launched in 2006, this bag was one of the first It bags to become a phenomenon. Like a successful Hollywood movie, it even spawned a sequel: French label Yves Saint Laurent (YSL) launched the more sedate Muse II in 2008, hoping to repeat the original bag's popularity.

10: The Downtown, by Yves Saint Laurent

Also launched by YSL in 2006 was the more casual and funky Downtown bag, recognisable through its buckled straps and prominent zippers. Like the Muse, the Downtown also inspired a derivative bag: the primmer Uptown bag aimed at a posher demographic.

11: Nylon backpack, by Prada

This staunchly minimalist bag made from parachute fabric may look nondescript now, but it was the height of cool at the time of its birth in 1985. The popularity of that little triangular Prada logo also marked the transition of this Italian brand into a much cooler phase led by Miuccia Prada.

12: The Speedy, by Louis Vuitton

It has been splattered with grafitti and plastered with cherries. No matter which incarnation of the Speedy you prefer, one thing never changes - its classic silhouette that never goes out of style. First introduced in the 1930s, it was originally used as hand luggage and its name refers to the rapid forms of travel of the time.

13: The Knot Clutch, by Bottega Veneta

This design is 31 years old, and the original version boasted a rectangular crystal clasp. The current clasp is modelled after a leather knot - to underline the brand's leather heritage - and was implemented by creative director Tomas Maier in 2001.

14: The Lady Dior, by Dior

Launched in 1995, this carrier is best known for being a favourite of the late Princess Diana, who reportedly owned one in every version and colour. Its stitched pattern is derived from the design of chairs once owned by designer Christian Dior and the lettered charms that dangle from its handle is another signature trait.

15: The crystal animal minaudiere, by Judith Leiber

The sparkling purses by Hungarian designer Judith Leiber were memorably mocked in an episode of TV series Sex And The City, but remain a firm favourite of ladies who lunch. One of her fortes is animal-shaped clutches covered with crystals.

16: The Bayswater, by Mulberry

It may have been born during the height of It bag fever in 2004, but this stylishly functional carrier from British brand Mulberry is one of the least obnoxious bags to emerge from those heady years. Its shape is simple yet distinctive and the signature turn-lock closure tastefully nods in the direction of the once-popular hardware trend.

17: Le Pliage tote, by Longchamp

This classic carrier is part of the Le Pliage line launched in 1993 and constructed to fold up neatly for easy packing ("pliage" means "fold" or "bend" in French). It is made of hardy nylon and available in a wide variety of prints and colours, including limited-edition versions by designers like Jeremy Scott.

18: The Bouvier, by Gucci

This Italian house renamed a line of chic hobo bags after former American First Lady Jackie Kennedy in 1961, as she was known to be a big fan of the design. Today, this bag is known as the Bouvier (Jackie's maiden name) and the latest spring/summer 2010 version has a futuristic vibe about it, with its punkish metallic embellishments.

19: The Bamboo bag, by Gucci

The first Gucci bag with bamboo handles was introduced in 1947 and was one way the brand coped with war-time rationing of more conventional materials. It was discontinued in the 1970s and re-surfaced in the late 1980s. For the recent spring/summer 2010 collection, creative director Frida Giannini introduced a sportier New Bamboo version.

20: I'm Not A Plastic Bag tote, by Anya Hindmarch

A 2007 creation by English designer Anya Hindmarch, this was produced in collaboration with an environmental group to discourage the use of plastic bags. It became a hot fashion item after it was chosen as the goodie bag for the 2007 Vanity Fair Oscar party.