Lent is the period of 40 days before Easter. It starts on Ash Wednesday and ends on Easter Eve (sometimes called Easter Saturday). But if you look in a calendar or diary and count the days they come to more than 40! This is because you don't count the Sundays in Lent!
For Christians, Lent is a time to prepare for Easter and to think about their relationship with God. It represents the 40 days when Jesus was tempted by the Devil in the desert. During this time he didn't eat or drink anything. Because of this, some Christians give up some food or 'fast' for Lent. For some people this is giving up all food and just drinking, but for others, they just give up luxury food like chocolate or cream cakes! The Eastern Orthodox Church sometimes calls Lent 'The Great Fast'.
During Lent in many churches, the altar is covered with a purple cloth. Purple is traditionally a royal colour and having a purple cloth on the altar helps people remember that Jesus is king and that he died at Easter. There are no flowers or any other decorations displayed in the church.
Lent started as a time that people that were being baptised, (a way of showing that you are a Christian). They would use Lent to prepare for their baptism on Easter Sunday. Over the years it has turned into a time of reflection and thought for all Christians.
In the U.K. and Ireland, and a few other countries, Mothering Sunday is always on the middle, or fourth, Sunday of Lent. In the countries when it's celebrated on this day it's also commonly called "Mother's Day".
(Many other countries have "Mother's Day" on different days in the Year. The most common one is on the second Sunday in May, but other dates include the 21st March - the Spring Equinox and 8th March - International Women's Day.)
In the 16th century, Mothering Sunday was the day when people were expected to visit their 'mother' church. This was the church were you had been baptised (christened as a baby) or your local parish church. If that was too far to travel, this could also then be the nearest cathedral to your 'mother' church (as cathedrals are seen as the mother church of all the local churches in an area).
Later it also became a day when servants and maids could have the day off work and go back and visit their families and especially their mothers. This might also have been done so that servants could visit their 'mother' church.
Now it is when Mums traditionally get the day off housework and have presents given to them.
The Last week of Lent is called Holy Week and helps people to think even more about the Easter Story.