According to the Quran, Allah "created man from a clot of blood" at the same time he created the jinn from fire (96:1-3). Muslims believe humans are the greatest of all creatures, created with free will for the purpose of obeying and serving Allah.
The Qur'an includes a version of the biblical story of the fall of Adam (Surah 7), but it does not conclude from it the doctrine of original sin as some Christian theologians have. In the Quranic version of the story, Adam and Eve begged God's forgiveness (7:23) and he punished them with a mortal life on earth but added, "from it [earth] you will be taken out at last" (7:25).
Since Allah forgave the sins of the first pair, Muslims believe that all people are born in Al-Fitra, a natural state of submission to Allah (Qur'an 20:122-23). True repentance from sin returns a person to this original sinless state.
According to Muslim theology, mankind's chief failing is pride and rebellion. In their pride, humans attempt to partner themselves with God and thereby damage the unity of God. Thus pride is Islam's cardinal sin. The cardinal virtue, then, is submission (islam in Arabic).