Beyoncé used the stage name Sasha Fierce for the alter ego introduced with her 2008 album I Am... Sasha Fierce.
Beyoncé described Sasha Fierce as a more performance-focused persona: confident, sensual, energetic, and uninhibited onstage. The album was structured as two discs, with I Am presenting more intimate ballads and Sasha Fierce emphasizing uptempo pop and R&B performances.
The project included “If I Were a Boy,” “Halo,” “Diva,” and “Single Ladies (Put a Ring on It).” The contrast between the discs helped communicate two sides of Beyoncé’s artistic identity, although she later said the boundary between herself and the persona had become less important.
Sasha Fierce is not Beyoncé’s fan nickname or a separate recording artist. “Queen Bey” and “Yoncé” are other names associated with Beyoncé, but the alter ego specifically linked to the 2008 album is Sasha Fierce.