What does the Sikhism religion believe?

I don't know a lot about this religion so if someone could tell me what they believe in and what the religion is about it would be greatly appreciated

It is Hinduism with some Islamic flavor.

The Muslims were killing the Hindus and Buddhists left right and center so the Sikhs were born as a warrior race to fight back. They always carry a dagger as a result.

They believe in One God.

Guru Nanek Dev is the founder of their religion.

Think Tanker has incorrectly said Sikhism is Hinduism with Islamic favor .

Sikhism is a monotheistic and pantheisticICCeligion formed 500 years ago , by Guru Nanak , who also is the first Guru of the Sikhs . Guru Nanak passed his succession of spirituality ( bestowed on him by god himself ) to 2ND Guru . 2ND guru passed to 3rd one and so on we have had 10 Human Gurus .
10Th Guru passed guru-ship to holy scripture , Guru Granth Sahib .

Sikhism basically believes in Working honestly , Meditating on name of God , Sharing with others .
Sikhism is also noticeable as one of the most friendly and tolerant religions . Sikhism not only tolerates other faiths , but also asks followers of other faiths to be achieve salvation while following their own religion . Sikhs have also sacrificed their lives for protection of poor , weak , needy , other faiths .
you can learn more here :
http://www.sikhs.org
http://www.sikhnet.com
http://www.allaboutsikhs.com