The Alberti bass is a style created by a composer named Alberti around 1700 to 1750. It is a method of breaking up a triad by playing the lowest note, then the highest note, then the middle note, then the highest note again. It can be played in quarter notes, eighth notes, 16th notes, or whatever.

Alberti Bass - Classical Piano Technique

This is very recognisable in some of Mozart’s compositions.

Ron