What is the purpose of zakat fitrah?

Zakat fitrah tithes in conjunction with Ramadan and Eid Fitr (Eid al-Fitr). Also named to zakat al-Abdan and ar-Ru-us (zakat body and head) as it is compulsory for every Muslim torso without exception whether big or small, old or young, male or female, rich or poor, free or slaves.

Zakat is compulsory on one bushel?

Zakat fitrah is required for all individuals whether male or female, minor or adult, free and slave, rich or poor, urban or rural people if enough conditions to be mentioned later.

For people who do not have dependents, charity inherently executed by the person himself or his maintenance. For those who have dependents, it must complete the zakat fitrah for himself as well as those who are under his maintenance obligation includes;

1. wife
2. Origin (ie father, mother, grandfather, grandmother next to above)
3. Offspring (the sons and grandsons), whether male or female, small or large / adult.
4. Owned slaves.

http://fiqh-am.blogspot.com/2009/09/zakat-fitrah.html