You could study style for years, and still have scope to learn more. It’s an interesting topic that doesn’t always get the love it deserves, with some dismissing it as frivolous. We wear clothes everyday (although a duvet day now and then is compulsory), and wearing something you love can often change your mood. In homage to the dynasty that is style, this A-Z guide will bring you a little insider information on one of our favourite subjects, this week concentrating on all things Y. Yves Saint Laurent Yves Saint Laurent has been lauded as one of the greatest fashion designers of all time. He was the first to introduce a tuxedo, designed primarily for women and he made clothes that were associated with peasants, such as the pea blouse, in luxurious fabrics. In 1955, Yves Saint-Laurent met Christian Dior, showed him some sketches and was hired on the spot. He then began working as his assistant. When Christian Dior passed away in 1957, Yves Saint Laurent was announced as his successor. 1962 saw him set up his own design house although it was 1966 before his designs were properly noticed, his couture pea coats and bell bottoms then received a standing ovation. However, in 1974, fame began to take its toll and uncomfortable with being recognised wherever he went, Saint Laurent began to shy away from public outings. 1977 saw Saint Laurent in and out of hospital, suffering from an addiction to both cocaine and alcohol. In July 1989, the Yves Saint Laurent company was successfully floated on the Paris stock market. He presented his final collection in January 2002. Yves Saint Laurent passed away from brain cancer in 2008. Yardley London  Yardley London is one of the oldest cosmetics, perfumery and toiletry companies in the world. It was established at the beginning of the 20th century and by 1910 it had moved to Bond Street in London. In 1967, British model Twiggy became the face of the brand and thanks to Yardley's stunning feminine campaigns it is appreciated by both fashion and beauty fans. Y.A.S Y.A.S is short for your Your Apparel Style. It's a high street brand with stylish separates "that make an outfit complete". Y.A.S adds an extra little bit of something to define a look, season or personality. It features eight collections a year and is an extension of the Vero Moda brand, offering fashion-forward styles and understated chic.