When I started on this road to learn Classical Arabic, I was told that there is only one Arabic and I am also told that when you speak Classical Arabic in Arabic speaking countries, you are thought to be weird and often you find yourself not understood. I do not point out as often that the second assertion negates the first and consequently there are many different Arabic languages. I do not yet understand to what extend the Koranic Arabic language is different from what is labelled "standard" Arabic language.
At this time I am learning to pronounce fully annotated texts. When you are used to Latin script, one of the lessons is that a space is not necessarily the dividing line between words. This is hard because it clashes with how you have learned to perceive a word at a glance. Al Arabiya or العربية shows two spaces but for me it is one word. To complicate it further, the vowels are missing and you need to know the Arabic grammar and vocabulary to know how to pronounce it with certainty.
Add to this the different ways Arabic is written and printed and you will appreciate learning the Arabic script for the intellectual challenges it presents.