The pre-Easter week and weekend is the most significant period in the Christian calendar, which commemorates the death and resurrection of Jesus Christ.
However, in modern times, it has also become associated with many secular and commercial activities, ranging from political rallies to special offers from supermarkets and other retailers.
For many people, the Easter period is essentially a spring holiday, but the religious aspect has survived down through the centuries and is still joyously marked by millions of Christians from many denominations throughout the world.
Easter is also linked symbolically with the Jewish Passover, to which Christ gave new meaning with the Last Supper prior to his arrest, trial and crucifixion marked by Good Friday and his resurrection from death and the tomb 'on the third day'.
The earliest evidence of Christians celebrating the Easter Festival comes from the middle of the second century, in a homily by Bishop Melito of Sardus in Western Anatolia, who was a recognised authority on early Christianity.
The tradition of celebration continued down the ages, but one of the early challenges was to set a date which would be agreed by the Church.
The first Council of Nicea in 325AD attempted to fix a date, with the complex formula of nominating Easter Day as the first Sunday after the Paschal full moon. In practice, however, the date of Easter in Western Christianity, according to the Gregorian calendar, generally falls between March 22 and April 25.
For centuries, this has caused difficulties for people in fixing Easter holidays, school terms and business arrangements, but a number of attempts to agree on a permanent date have proved unsuccessful.
As if this was not complicated enough, the Eastern churches historically based their calculations on the Julian calendar and they celebrate Easter between April 4 and May 8.
In the United Kingdom, the Easter Act of 1928 set out to legislate for a date between April 9-15 and, although this remains on the statute book and could be implemented with the agreement of the churches, a set date for Easter seems as far away as ever.
In 1977, the World Council of Churches met in Aleppo in Syria, now torn asunder by a terrible civil war, and suggested a clearer schedule for the celebration of Easter, which was to begin in 2001. So far, however, nothing has happened.
The divergence of views over Easter, though not its meaning, is reflected by the approaches of different Christian denominations. During Holy Week, many churches hold nightly meetings and acts of worship in these preparation for Easter and they culminate in the solemn services on Good Friday.
The Roman Catholic and many Anglican churches also hold Easter services on the Saturday and the centrality of the entire Festival reaches its peak on Easter Sunday.
In many places, Easter Day begins with sunrise services, a tradition thought to have started in 1732 among a group called the Single Brethren in a Moravian congregation in Saxony.
In the past 40 years or so, this tradition has been maintained by many denominational and inter-denominational groups in Northern Ireland. This year, for example, the Presbyterian Church will be associated with a wide range of such services in venues from car- parks to coastal slipways and in places ranging from the Cloughmore Stone above Rostrevor, to Spelga Dam, Ballintoy Harbour and Second Donegore Presbyterian Church in Co Antrim.
These services attract thousands of people of all ages and in many areas they are followed by a hearty breakfast in local church halls. They also provide good opportunities for developing contacts and for sharing friendships in the early hours of an often inclement Ulster Easter Sunday morning.
However, the ecclesiastical significance of these services was well summarised by the Presbyterian Moderator, Dr Rob Craig, who said this week: "Rising early on Easter morning and gathering with others to worship, celebrate and give thanks as the sun rises, makes for a very special way to mark Christ's resurrection.
"In a way, we are connecting with the first women who came and found the empty tomb, and joining with them in proclaiming the good news of the risen Lord to the whole world."
In spite of these celebrations by thousands on Easter morning, there are other Christians who choose not to mark this as a special day. The Quakers ( the Religious Society of Friends) do not observe Easter or any other major Christian festival, in the belief that it is wrong to elevate one day above another and that every day is the Lord's Day.
In Eastern Christianity, the celebration of Easter is slightly different. The Eucharist service is preceded by a procession symbolising a futile search for the body of Christ.
This leaves the church in darkness, but when the worshippers return, the lights are on everywhere. The symbolism of the light conquering the darkness is there for all to see.
One of the features of the Christian Festival in many countries, secular and non-secular, is that Easter Monday is a public holiday. For Christians, the joy and reflection of the Easter message in the previous day's services is followed by the relaxation afforded by a national holiday.
For non-believers, Easter Monday and the next few days provide an opportunity to celebrate with family and friends. Because of the extended holiday period many people go abroad, or travel to camping sites and caravan parks nearer home.
The Easter period also provides a good opportunity for extended shopping, which is the modern religion, in which the supermarkets and commercial centres have become the secular cathedrals of the 21st century.
In Ireland, north and south, Easter also has a special and strictly non-theological dimension. This is the period when republicans commemorate the Easter Rising of 1916 in Dublin, and the Easter lilies become almost a badge of honour for those with pan-Irish aspirations.
Not surprisingly, Easter is important for the unionist community and this period generally marks the beginning of the annual marching season by the loyal orders, which usually brings with it the shadow of limited but often very serious inter-community confrontation.
In an increasingly secular Western world, where materialism threatens to be taking over, it is difficult to predict how Easter will develop in the future.
Certainly it will not die out, because the commercial world is so wedded to the exploitation of such a long-established holiday season. The same applies, of course, to the other major Christian festival of Christmas.
For true believers, however, the celebration of Easter will never die out and it is important to remember that, to millions of Christians in the developing world, this period will remain a central part of their deep faith – a point which so many secularists in the West fail, or chose not, to recognise.
The importance of Easter, whatever its connotations or non-connotations for believers and non-believers, will continue as a unique and cherished part of our shared culture and that is not likely to change any time soon.
Easter is a period for worship, for rejoicing, for togetherness and for enjoyment for everyone. Long may it remain so.
Alf McCreary is the Belfast Telegraph's religion correspondent