Judaism has many sects like most other religions.
There are different denominations based on how religious you are:
Hasidic, (Modern) Orthodox, Massorti, Reform and Liberal, in order from most observant to least. Orthodox means traditional and can be used as a term to describe all of the first three. Reform means they change with the times and this can be seen to cover both reform and liberal movements. Liberal Judaism can also be referred to as Progressive Judaism.
In America, the largest denomination is Reform, whereas in the UK, it is Modern Orthodox.
The Hasidic Movement is the eldest, next the Reform Movement (19th century). Orthodox was founded in response to reform. Liberal was founded in 1902 and Massorti is only a few decades old.
They all believe in the word of the Torah and consult the Talmud for help on how to lead their lives. They differ in belief over Women's roles, language that the service should be read in etc.