Difference between jacket and coat

A blazer can be considered a sub-category of sports jacket The original blazers were brightly colored and boldly patterned striped and/or piped school jackets. These single-breasted jackets were widely used as school, house, club, and team uniforms in British schools and colleges and were called blazers because their colors set the rivers "ablaze" at rowing competitions. Such jackets (of wool or cotton, often including a school or club insignia on their chest pockets) are today often called "college blazers," or "club blazers." The other garment usually called a blazer today is derived from naval uniforms. Sometimes called a "reefer blazer" in reference to the reefer jackets from which it is descended. This blazer was originally double-breasted, navy blue wool serge, with brass buttons (often engraved with a club insignia) and closely resembled the dress uniforms of Royal Navy petty officers. It was originally used by yachtsmen and other boaters - from which it became something of an icon of leisured affluence. Later single-breasted versions, flat black or silver buttons, other colors (including other blue shades), and other fabrics came into use. Sports jackets can include these two types of blazers, but also includes jackets that are checked, corduroy, tweed, and other patterns and fabrics derived from other kinds of sport or country pursuits. Prominent styles or features are derived, for instance, from hacking jackets (for riding), shooting jackets, and Norfolk jackets. Originally worn with matching pants, as this "leisure suit" became tamed for town and business wear (displacing the more formal morning dress and frock coat ensembles), the mismatching of the "odd jacket" and "odd trousers" became the new informal.