Lo-fi(from the term "Low fidelity") is a term used to describe music in which the sound is of a lower quality than the usual standard. The qualities of lo-fi are usually achieved by either degrading the quality of the recorded audio, or using certain equipment. Recent uses of the phrase have led to it becoming a genre, although it still remains as an aesthetic in music recording practice. Many lo-fi artists use inexpensive cassette tape recorders. The term was adopted by WFMU DJ William Berger who dedicated a half hour segment of his program to home recorded music throughout the late '80s under the name Lo-fi.

As a term to describe a musical genre, lo-fi is mainly associated with recordings from the 1980s onwards, when cassette technology such as Tascam's four-track Portastudio became widely available. Prime early exponents included Daniel Johnston, New Zealand bands such as the Tall Dwarfs, who recorded on Chris Knox's 4-track and released on Flying Nun Records, and Beat Happening and the Olympia, Washington label K Records. In the early-mid 1990s (1991вАУ1998), Lo-fi found a wider audience with the success of such acts as Beck, Blur, Sebadoh, Guided by Voices, Smog, Mercury Rev, Pavement, Modest Mouse, Liz Phair, Will Oldham, Yo La Tengo, Jon Spencer Blues Explosion, Ween, David Kilgour and (later) (1999вАУ2003) Elliott Smith, Neutral Milk Hotel, The Apples in Stereo, Dr. Dog, The Olivia Tremor Control, Elf Power, Beulah, Of Montreal, Mike Rifone, Sufjan Stevens and The Shins.

Often lo-fi artists will record on old or poor recording equipment, ostensibly out of financial necessity but also due to the unique aural association such technologies have with "authenticity", an association created in listeners by exposure to years of demo, bootleg, and field recordings, as well as to older pop studio recordings produced more simply. The growth in lo-fi coincided with the growth of extreme slickness and polish associated with the multitrack pop recording techniques of the 1980s.

Currently, there is a growing scene of lo-fi bands in the United States and Canada. This recent wave of artists has been given the name shitgaze, due to the notable shoegaze influence as well as the extremely low-budget recording techniques. Notable bands and solo artists include Two Gallants, Wavves, No Age, Times New Viking, Rogue Wave, Best Coast, Gonjasufi, Vivian Girls, Former Ghosts, Zola Jesus and Glass Graves. There is also an even newer trend of Lo-fi Goth bands, which incorporate influence from Noise, deathrock, new wave, and hardcore punk. This scene grew out of an influx of ex-deathrock revivalists into the indie music scene.