Arminianism or Calvinism?

Basically they are two different theological views regarding God's role and our own in the whole process of salvation. Both are based on the Bible, but the differences arise due to their interpretation of what the Bible says. Calvinism was popularised by John Calvin (1509-1564) who was a French reformer, and followed after Martin Luther (1483-1546) who initiated the Reformation. Arminianism is named after Jacob Arminius (1560-1609) who was a Dutch theologian. But what are Calvinism and Arminianism? What are the differences? And why does it matter? And is there a third position? A blend of both?