Only a handful of people claimed to have successfully contacted Jandek before he began regularly playing in public (see below). He releases albums through his own record label Corwood Industries, keeping a Houston post office box so fans can write to Corwood for a typewritten catalogue and order Jandek’s albums, usually at inexpensive prices. Many of his albums feature pictures of a certain man at various ages; although it seemed likely, it was not until Jandek's live debut in 2004 that it became certain that the man depicted on the album covers was the principal performer.

Jandek now often performs live with other musicians, but these collaborations remain the extent of his engagement with the public.

Although never formally confirmed, it is widely accepted that Jandek's real name is Sterling Richard Smith (probably born October 26, 1945); a review of Ready for the House in OP magazine, the first ever national press given to Jandek, refers to the artist as Sterling Smith, checks written to Corwood come back endorsed by Smith, and Smith is listed as the claimant in the copyright records for Jandek's albums at the Library of Congress. Despite this evidence, Corwood never uses the name in connection with Jandek, and, in turn, many of Jandek's fans respectfully maintain this separation. He is widely believed to live in the area of Houston, Texas, as this is the location of the post office box (No. 15375) which has been used by Corwood from the beginning. There is also a telephone number for Corwood Industries listed in the phone book for the area. Corwood happens to share the number with "Sterling Smith Corporation", which appears to be a stock and securities broker.

Smith has kept his personal history an almost absolute secret, revealing only one story about his pre-Corwood years: he wrote seven novels but burned them upon rejection from New York publishers. Aside from that anecdote, virtually nothing is known about his life. He is rumored to have grown up, or at least spent time, in Providence, Rhode Island. This suggestion is not baseless – a handful of early Jandek songs mention either the state itself or the Rhode Island town of Point Judith. It has also been suggested that he is well traveled, as several album sleeves depict locations that have been formally identified as being outside the United States. This, however, presumes that all pictures that do not depict Smith were taken by him.

In one of his just two known interviews (given in 1985 to John Trubee for Spin Magazine), Jandek mentioned that he was working at that time as a machinist.

Jandek's first album, Ready for the House, though obviously a solo work, was originally credited to a band called The Units. As explained in an interview in the first issue of Spin, Smith was forced to change the name by an identically named Californian group already in possession of a copyright. All reissues of this first album and all subsequent Corwood releases have been credited to "Jandek". In Trubee's interview, Smith claims he came up with the name Jandek while on the telephone with a person named Decker during the month of January. Smith's initial use of a plural band name (and Corwood's curious tendency to refer to Jandek as "a representative from Corwood Industries") has led some fans to suggest that the reclusive artist intended his oeuvre to be perceived as the work of an anonymous collective rather than that of a single man. Indeed, though roughly two-thirds of his records are solo affairs, the other third have variably featured female vocalists, different male vocalists, bass guitar, electric guitar, drums, and accordion. These contributions are usually credited to outside collaborators, but in the Spin interview as well as a letter to DJ Irwin Chusid the artist admitted to having overdubbed parts himself on occasion, such as on the album The Rocks Crumble. No proper credits list has ever appeared on an album, but song titles have included "Nancy Sings" and "John Plays Drums", though those pieces are two different versions of the same song.

One early theory suggested that all the music was recorded in a single, feverish, possibly manic phase and that after 19 albums the releases would stop. This appeared, for a moment, as if it might have some validity - the 21st album, Lost Cause, finished with a sidelong piece called "The Electric End", a crazed instrumental featuring shouted vocals, electric guitar, and microphone feedback. Instead, this seems to have marked the end of the "first band phase." Then the 22nd album arrived and returned to the acoustic and vocal sound that is found on most of the first six Corwood albums (often referred to as "the first acoustic phase"). This continued unabated for seven albums until, in 1999, The Beginning was released, which featured a side-long work of instrumental piano. This ushered in the most controversial period of albums in Corwood's history - three albums of unaccompanied voice. Seemingly recorded on a voice-activated tape recorder, these "spoken word songs" ran up to half an hour in length and taxed even the most devoted followers. After these albums, though, the direction changed again and Jandek returned to a voice and guitar (with occasional harmonica) mixture, though things were different. The guitar was often electric and the voice was decidedly older than that on the previous albums. Further albums have continued the solo approach, though the instrument used has occasionally been a fretless bass, and the songs have stretched progressively longer and the lyrics have become even more personal. Though Corwood still releases albums like this (the most recent is What Was Out There Disappeared), they are now alternated with releases of the live band shows, which are remarkably different and feature unusually tight playing.

Some of Jandek's allure stems from his small but devoted fan base that includes Sonic Youth, Bill Callahan, Mike Watt, John Darnielle of The Mountain Goats, Low, Ben Gibbard of Death Cab for Cutie, Matt Cameron of Pearl Jam, Bright Eyes and K Records founder Calvin Johnson. In the 1980s and 1990s most fans stumbled into the world of Jandek after hearing his music on college radio or freeform stations like WFMU and WCBN-FM, but as the 21st century approached Jandek was just as likely to catch fans through the internet. An "unofficial Jandek website" was founded by Seth Tisue in 1997. It includes complete descriptions of each album and concert and the archives of the Jandek Discussion List.

Jandek has given only two phone interviews in his entire career, the first conducted by fellow outsider artist John Trubee, for the aforementioned Spin article in 1985. In it, he admitted to having had musical training earlier in life, and refuted an OP magazine reviewer praising "May he never tune his guitar!" by stating that he did indeed tune his guitar, albeit usually to open tunings of his own devising. The Spin article was Jandek's first major press; as the '80s drew to a close, the magazine proclaimed him to be one of the Most Important Artists of the 1980s in a special end-of-decade issue. Outsider music expert Irwin Chusid conducted the second interview and brought quite a bit of attention to Jandek by including an account of his own dealings with Corwood Industries in his book Songs in the Key of Z: The Curious World of Outsider Music, the accompanying album featuring a track from Ready for the House after Jandek called him in response to Chusid's request for information. Texas Monthly reporter Katy Vine tracked down the "Corwood Representative" and gave an account of her experiences in the August 1999 issue. At Jandek's request Vine kept his name and address a secret.

In 2004 Unicorn Stencil Productions released the first documentary on Jandek, entitled Jandek on Corwood. It was directed by Chad Freidrichs, and produced by Freidrichs and Paul Fehler. Amongst the extras on the DVD release of the documentary is the entire unedited tape of the John Trubee-conducted Spin interview. No one from Corwood Industries is represented on screen, but the label did suggest several people to be interviewed for the movie, including music critics Phil Milstein and Gary Pig Gold, and Katy Vine. Corwood's recommendation of Vine for the documentary is seen as essentially endorsing the contents and confirming the authenticity of the Texas Monthly interview. In October of the same year Jandek stunned the alternative music scene by playing live for what was probably the first time (see live performances section below for details).