Key of A: A Bb C# D E F G A
Below is the pattern for the Arabian scale using whole and half steps.
W= whole step, h = half step, m3 = 3 half steps ( or a whole step + a half step ).
h m3 h W h W W
A ^ Bb ^ C# ^ D ^ E ^ F ^ G ^ A
Half steps: half steps on a piano are the distance between any two adjacent keys, white or black.
Whole steps: a whole-step is two half-steps combined. A whole-step above a key on the piano is two keys to its right, while a whole-step below a key on the piano is two keys to its left.
What we call the Arabian scale comes from the middle east. The scale or Maqam is called Hijaz Nahawand. The term Hijaz refers to the first Jins, or scale fragment that the maqam is built from, in this case, the first four notes of the Maqam. Nahawand refers to the second Jins, which happens to contain five notes which begin from the fourth scale degree of the Hijaz. Typically Jins are made up of four consecutive notes (tetrachords), although three and five notes jins also exist. Hijaz Nahawand is one of the main Maqam of the Hijaz Family. In western music theory this scale is called the Phrygian Dominant. It is the fifth mode of the Harmonic Minor scale. To think of it from the modes of the major scale, it is a Phrygian mode with the third scale degree raised up a semitone or half step.
Maqam = scale.
Jins = a subsection of a scale that contains 3,4 or 5 consecutive notes that can be used to create scales in different combinations of Jins.
Hijaz = four note Jins or known in western music theory as a tetrachord.
Nahawand = five note Jins or known in western music theory as a pentachord.