Complex sentence: Arabic is written with the Arabic alphabet, which is an abjad script, and is written from right-to-left although the spoken varieties are sometimes written in ASCII Latin from left-to-right with no standardized forms.
Split into simpler sentences: Arabic is written with the Arabic alphabet, which is an abjad script, and is written from right-to-left. Although, the spoken varieties are sometimes written in ASCII Latin with no standardized forms.