The Melodic Minor is a strange scale because the basic concept of it is that you go up (ascept) the Straight Melodic (the scale below) and then down (descend) the Natural Minor. As weird as this seems it actually sounds pretty good. Personally to lessen confusion I just like to think of the Melodic Minor as the Straight Melodic, where you go up and down the same scale. It makes way more sense! You can use this scale in whatever way you like, but having said that it is used a lot in jazz music simply because it's a little odd sounding. Not to say that you shouldn't learn it because you don't like jazz music, it's always good to have a large knowledge of different scales! Remember, use the economy picking method for this scale.
Melodic Minor
First Mode
Minor
1st 2nd b3rd 4th 5th 6th 7th
Phrygian #6
Second Mode
Minor
1st b2nd b3rd 4th 5th 6th b7th
Lydian Augmented
Third Mode
Major
1st 2nd 3nd #4th #5th 6th 7th
Lydian Dominant
Fourth Mode
Dominant
1st 2nd 3rd #4th 5th 6th b7th
Fifth Mode (no common name)
Fifth Mode
Major
1st 2nd 3rd 4th 5th b6th b7th 
Locrian #2
Sixth Mode
Major
1st 2nd b3rd 4th b5th b6th b7th 
Altered Scale
Seventh Mode
Minor
1st b2nd b3rd b4th b5th b6th b7th 
