Many of the skills and abilities shown in Dragonball are performed using the advanced knowledge of Energy manipulation. In DBNU, skills are performed using Ki, Energy, or Mana.
Most living beings possess a natural energy called Ki (sometimes Chi) that is used in everything from flight to transformations and notably beam attacks. Most of the playable races in DBNU
Some beings instead have an Energy supply. Androids have an internal battery that allows them to generate energy for skills. Fierian Demons, lacking a truly physical form, also use basic 'Energy' rather than 'Ki' energy.
Wizards are unique in that they possess a pool of Mana that they use to perform skills and spells.
See Also: Stats, Powerlevel