Ekadasi is a Sanskrit word for number 11. It means the 11th day of each half of the month in the Vedic lunar calendar. So there are two Ekadasi days in each month on the Vedic calendar. One is in the first half of the month whilst the moon is waxing, or growing. This is known as the bright fortnight. The second  is in the second half of the month whilst the moon is waning, or shrinking. This is known as the dark fortnight.
Ekadasi has been set aside for us to observe a fast to please Krishna and is a special day for devotees. Bread, pasta, lentils, rice, as well as beans and preparations made from bean flour doesn’t eat on ekadasi.
We can fast on Ekadasi  in order to minimize the demands of the body so we can engage more of our time in the service of the Lord by chanting or performing  some other devotional service. The best thing to do on  these fasting days is to remember the pastimes of Krishna and to hear His Holy name being sung and chanted. On the day of Ekadasi we should plan to chant more rounds and read more devotional literature.  If possible we should spend more time with devotees.
So as we can see Ekadasi is a time for us to develope our spiritual  capacity. lIt is a time for us to increase our practice and to put a little more effort into our devotional service.