Tallaght was founded as a monastery by St. Maelruain in 769 AD, It was devastated by the Vikings in 811 AD.
In the 1960s, Tallaght developed from a small village to a large town in South Dublin, and in 1994, South Dublin County Council (SDCC) was formed with a headquarters in Belgard, Tallaght.
"Greater Tallaght" comprises Tallaght village and a range of areas that were formerly small settlements (Jobstown, Old Bawn, Kilnamanagh) and rural townlands, all developed in recent decades.
The original village of Tallaght lies west of the Tallaght Bypass (N81). It stretches east-west from Main Road and Main Street to the Abberley Court Hotel at the end of High Street and encompasses the Village Green shopping plaza, Tallaght Courthouse, Westpark, and many shops, restaurants and banks. It also houses Tallaght Youth Service, Tallaght's first newspaper printing house the Tallaght Echo, and (formally) Tallaght Community Arts Centre. The area's Institute of Technology, Saint Mary's Priory, and Saint Maelruain's Church are located in the historic quarter of Tallaght village.
The newer "town centre" lies immediately to the south across the Belgard Road, encompassing Belgard Square, the main shopping complex (known as The Square also known as the Pyramid), the Luas Red Line terminus, Tallaght Hospital (including the National Children's Hospital), County Hall, the Civic Theatre, South Dublin County Library, Rua Red Arts Centre, and several bars, restaurants and hotels.
To the northeast of the village lies the Tymon North / Balrothery area, which comprised rural townlands until the 1970s. This district includes estates such as Bancroft, Balrothery, Glenview, Castle Park, Saint Aongus, Tymon, Bolbrook and Avonbeg. These parts are home to several sporting facilities, including the National Basketball Arena, a fitness centre, two swimming pools, an athletics track, and an astroturf football facility. Tymon Park is watered by the River Poddle and is Ireland's second-largest city park. It borders Greenhills and Templeogue, and it contains extensive sporting grounds, ponds, Coláiste De Hide and one of Ireland's largest playgrounds at the Tymon North entrance.
Old Bawn, formerly a small village in its own right, is immediately south of the village, bordered by Sean Walsh Memorial (also locally called Watergate) Park. To the east of Old Bawn, estates include Home Lawns, Mountain Park, Millbrook Lawns and Seskin View. To the south and southwest of the village lie Kiltipper, Aylesbury, and Killinarden (the latter comprising the residential areas of Deer Park, Cushlawn, Donomore, Killinarden Estate and Knockmore). Beyond these are rural lands, running towards the Wicklow Mountains.
In the northwest is Belgard Green, with Belgard Heights and Kingswood (built 1974) to the north, Kingswood is also sometimes considered as Clondalkin and half holding a D22 postcode. Half of Kingswood is served by Clondalkin Garda Station. Kingswood and Belgard Heights are adjacent to Clondalkin, while Kilnamanagh is situated beside Greenhills and south-west of Walkinstown and Crumlin. Tallaght Theatre is situated along Greenhills Road.
Virginia Heights and Springfield are close to the area's centre, and further west of the town centre is the former hamlet of Jobstown, now with dense housing estates, and also the recently rural areas of Kiltalown, Brookfield and Fettercairn.