In jazz, there are 3 different types of minor scale: The Natural Minor, The Melodic Minor and the Harmonic Minor. Each of these 3 scales serves a specific purpose and application in jazz and so it is important that you know how to construct these scales.
The natural minor scale contains the same notes as the major scale. The only difference is that it starts on a different note. If you play a major scale from the 6th to the 6th note, you will have the relative minor scale or natural minor scale – both of these terms refer to the same scale.
The harmonic minor scale is the same as the natural minor scale but with a raised 7th degree. By raising the 7th degree, the scale has a stronger harmonic foundation and can be used to create more interesting harmonies that the natural minor scale.
The melodic minor scale is is the natural minor scale with a raised 6th AND 7th degree. Another way you could look at this is the major scale with a flat 3. The raised 6th and 7th degree creates a very smooth flowing scale which is why it suited to jazz improvisation.