In contemporary usage, it usually involves dancing and playing Gaelic folk music, either at a home or a larger concert at a social hall or other community gathering place.
The 'ceilidh' is a literary entertainment where stories and tales, poems and ballads, are rehearsed and recited, and songs are sung, conundrums are put, proverbs are quoted, and many other literary matters are related and discussed The ceilidh of the Western Hebrides corresponds to the veillée of Lower Brittany ... and to similar story-telling festivals which formerly flourished among all the Celtic peoples On long, dark winter nights it is still the custom in small villages for friends to collect in a house and hold what they call a "ceilidh" (pronounced kay'lee).
Young and old are entertained by the reciters of old poems and legendary stories which deal with ancient beliefs, the doings of traditional heroes and heroines, and so on.
The use of these or similar terms is still the form in much of Ireland and Hebridean Scotland, and at gatherings elsewhere at which either Irish or Scottish Gaelic is the predominant social language.
Cèilidhean are sometimes held on a smaller scale in private or public houses, for example in remote rural areas and during busy festivals.
Cèilidh music may be provided by an assortment of instruments including fiddle, flute, tin whistle, accordion, bodhrán (frame-drum), hammered dulcimer, and in more recent times also drums, guitar, mandolin, bouzouki, Scottish smallpipes, and electric bass guitar.
The basic steps can be learned easily; a short instructional session is often provided for new dancers before the start of the dance itself.
These can be performed by fixed couples or in the more sociable "progressive" manner, with the lady moving to the next gentleman in the ring at or near the end of each repetition of the steps.
Some of the dances are named after famous regiments, historical battles, and events, others after items of daily rural life.
The "gay Gordons", "siege of Ennis", "walls of Limerick", and "stack of barley" are popular dances in this genre.
The cèilidh has been internationalised by the Scottish and Irish diasporas in Canada, the United States, Australia, and New Zealand, where local cèilidhean and traditional music competitions are held.
Privately organised cèilidhean in the 2020s are extremely common in both rural and urban Scotland, where bands are hired, usually for evening entertainment for a wedding, birthday party, celebratory or fundraising event.
The appeal of the Scottish cèilidh is by no means limited to the younger generation, and dances vary in speed and complexity to accommodate most age groups and levels of ability.
Plentiful branches of the Gaelic League giving dance, singing, music, and literature classes were established across Ireland.
At the end of one whole iteration of the dance (lead around and body), instead of stopping, the groups move on to the next set of partners in the line.
Céilí dances that can be performed progressively are: walls of Limerick, siege of Ennis, haymaker's jig, and fairy reel.
Embellishments are accepted and fun in social céilí dances, women adding spins or changing the style of a swing based on the skill of a partner.
An experienced ceilidh caller will have a good understanding of the mechanics of the tunes and a deep knowledge of regional dances from the UK and beyond.
During an English ceilidh there is often an interval involving the talents of local Morris or rapper side; this also serves to give bands with older members a rest.