Technical accessibility and a Do it yourself (DIY) spirit are prized in punk rock. UK pub rock from 1972-1975 contributed to the emergence of punk rock by developing a network of small venues, such as pubs, where non-mainstream bands could play. Pub rock also introduced the idea of independent record labels, such as Stiff Records, which put out basic, low-cost records. Pub rock bands organized their own small venue tours and put out small pressings of their records. In the early days of punk rock, this DIY ethic stood in marked contrast to what those in the scene regarded as the ostentatious musical effects and technological demands of many mainstream rock bands. Musical virtuosity was often looked on with suspicion. According to Holmstrom, punk rock was "rock and roll by people who didn't have very many skills as musicians but still felt the need to express themselves through music". In December 1976, the English fanzine Sideburns published a now-famous illustration of three chords, captioned "This is a chord, this is another, this is a third. Now form a band".