It is the principal commercial and farming town on the island – the larger town of Holyhead being a port town and somewhat separate from the agricultural, cultural and linguistical nature of the rest of the island – and in the past hosted the largest cattle market on the Island.
The town lies at the centre of the island on the River Cefni, after which it is named, and is home to the Oriel Ynys Môn museum, detailing the history of Anglesey and housing the legacy collection of Charles Tunnicliffe. In the west of the town is a large secondary school, Ysgol Gyfun Llangefni (Llangefni Comprehensive School), and in the north a Victorian church, St Cyngar's, set in a wooded riverside location known as The Dingle. The church provided the former name of the town, Llangyngar.
There is a relatively large industrial estate housing a chemical manufacturer, a slaughterhouse and other small businesses. The town had a station on the Anglesey Central Railway line which opened in 1864. It closed in 1964 with the closure of the line although goods trains continued to pass through the town until 1993. Although no longer used, the tracks have not been removed.
This town also has a college, Coleg Menai (Llangefni Site). Water for the town comes from Llyn Cefni (Lake Cefni), one kilometre to the north.
Football : The local football team, Llangefni Town, was promoted to the Welsh Premier League at the end of the 2006/7 season, but relegated after a single season in the top flight. Llangefni is also home to Wellmans Football Team that plays on Sundays in the North Gwynedd and Anglesey League : I and H Griffiths Premier Division.
Rugby : Llangefni is also home to Llangefni RFC a rugby team that plays in the WRU leagues. The club recently gained promotion to Division 3 West, but this has been hampered by the WRU's decision to demote the club back to Division 4 North Wales league.