Paul Weller (born John William Weller) and Rick Buckler met at school in Woking, Surrey, in 1975 and played music together during their lunch hours.
The pair joined up with Bruce Foxton - who had been playing in a local prog rock band called Rita - and Steve Brookes to play local pubs and clubs, but Brookes soon quit, leaving the band as a trio.
The Jam signed to Polydor in February 1977 for £6,000 and their first album In The City went Top 20 in the UK.
Their second LP, The Modern World, was something of a disaster, and everybody involved acknowledged that Weller's songwriting muse had disappeared.
When their A&R man heard their new recordings, he bluntly told them to scrap it. They did, but the breathing space this created, and the pressure they were now under, forced Weller to take stock - with astonishing results.
The first result was a single, a double-A side comprising The Kinks' David Watts and a new Weller song, 'A' Bomb In Wardour Street. This was followed by another single, Down In The Tube Station At Midnight.
The transformation was complete - instead of blustering observations and naive politics, Weller's songs were now mini-operas; Mindless violence in a punk club, being mugged on the way home. The songwriter and the listener were central to the action.
All Mod Cons (1978) turned The Jam into the nation's favourite band overnight and they became the punk era's very own Beatles: an unstoppable hit machine that made records that mattered, and charmed British youth without a whiff of compromise.
The album presented twelve three-minute vignettes delivered with a crisp, sharp modernist attitude. Get in, do it, get out; no slack, no frills, no pretty stuff. And no sneering.
Weller created characters, filled them in, made them breathe, then watched the modern world dump on them; the pop star on his uppers (To Be Someone), the aspirational suburban drone (Mr. Clean), a Walter-Mitty-like dreamer (Billy Hunt), the poor sod drowning in consumerism (In The Crowd) - there was even a tender love song, English Rose, about which Weller was so embarrassed it was not listed on the LP sleeve.
Their supremacy was revealed in the band's fourth album, Setting Sons (1979), on which the anthemic Eton Rifles concisely articulated the class war with which Weller now seemed obsessed. The album went to #4 in the UK (#137 in the USA).
In March 1980, while touring in Texas, the band learned that their next single, Going Underground, had entered the UK chart at #1. Polydor jumped on the song's success and re-released six of The Jam's earlier singles, all of which charted for a second time.
The next new single, Start! - which followed Going Underground to #1 in September 1980 - sailed pretty close to The Beatles' Taxman but, to be fair, Weller always admitted to practising the ultimate form of flattery.
With yet another UK and European tour on the horizon, The Jam put out a fifth album - Sound Affects (1980). This was a funkier work than anything previously attempted and contained Weller's magnum opus That's Entertainment.
While not a formal concept album, taken together, the songs from Sound Affects form a portrait of the disgruntled yearning that is central to the complaint of the Angry Young Man™. From the empty consumerism of Pretty Green to the bitter Scrape Away, the listener enters a world of failed potential.
A quieter period followed in 1981, though the singles Funeral Pyre and Absolute Beginners both reached #4 in the UK and the year ended with The Jam winning just about every award in the NME poll for the second successive year.
In 1982 the band returned to #1 in the UK singles chart with the chunky bass-driven Town Called Malice. The track graced The Gift - an album that had a warm, 'live' rock/soul sound and sourced its rhythms from black music styles like calypso and Motown.
The Gift was promoted by a tour complete with backing singers and a brass section, but that was to be the end of the line: Foxton and Buckler were informed by Weller in June 1982 that he was leaving the group.
Appropriately the next single released was the intentionally trite love song The Bitterest Pill. A lengthy farewell tour followed, and The Jam's final single, Beat Surrender, entered the UK chart at #1, coinciding with the band's emotional last gig at the Brighton Centre on 12 December.
Obliged by Polydor for one further album, The Jam provided Dig The New Breed, a live anthology which didn't quite capture their power and intensity. Polydor also re-released all thirteen Jam singles, which in a remarkable feat reached the UK Top 100 simultaneously.
A greatest hits package, Snap, served as conclusive proof of the band's consistent quality over seven years.
Bruce Foxton released a single inspired by the life of the Elephant Man, called Freak, and a solo album before ending up with fading punks Stiff Little Fingers.
Rick Buckler attempted to continue a musical career with Time UK before running a studio and finally his own furniture restoration business.
Foxton and Buckler reunited in the new millennium, performing as 2/3 of an outfit called From The Jam.