Ramadan is celebrated because it is very holy and important month for Muslim . It is Observed for Spiritual growth,self discipline and to remember the blessings of God (Allah)

Main reason why Ramadan is celebrated
Revelation of the Quran
Muslims believe that the holy book Quran was first revealed to Prophet Muhammad during the month of Ramadan. That is why this month is considered very sacred
Fasting (Roza)

From dawn (sehri) to sunset (iftar) Muslims keep fast. This teaches
- Self control
- Patience
- Discipline
To feel for the poor
Fasting helps people understand the hunger and difficulties of needy people, encouraging charity ( Zakat and Sadaqah)
Worship and Forgiveness
Muslims pay more read the Quran and ask Allah for forgiveness and blessings.
Spiritual Purification
Ramadan is a time to avoid bad habits speak good words and become a better person.
Ramadan is celebrated for fasting prayers, charity, self control and spiritual closeness to Allah.
Eid -ul-fitr is directly connected to Ramadan because it marks the end of the month of fasting.

End of Fasting
After Muslims fast for the whole month of Ramadan the next day (when the new moon is seen is celebrated as Eid -al-Fitr .It is a celebration of success full competing the fasts.
Thanking Allah
Eid is a day to thank Allah for giving strength to complete Ramadan with Patience and devotion.

Charity
Before the Eid prayer Muslims give special charity called zakat -al-Fitr. This ensures that even poor people can celebrate Eid Happily.
Celebration After worship
Ramadan is about prayer, fasting and self control. Eid is the joyful reward after one month of devotion.
Ramadan is the month of fasting and worship and Eid-al-Fitr is celebration that comes immediately often ends.