Wikipedia is one of the most widely used information sources in the world. Although one of the guiding pillars of this digital platform is ensuring access to the diversity of human knowledge from a neutral point of view, there is a clear and persistent gender bias in terms of content about or contributed by women. The challenge is to include women as equal partners in the public sphere, in which Wikipedia is developing a central role as the most used educational resource among students, professionals, and many other profiles. In this paper, we introduce the gender perspective in the analysis of the gender gap in the content and participation of women in Wikipedia. While most studies focus on one of the two dimensions in which the gender gap has been observed, we review both approaches to provide an overview of the available evidence. Firstly we introduce how the gender gap is framed by the Wikimedia Movement strategy, then we evaluate the gender gap on content and participation, especially regarding editor practices. Finally, we provide some insights to broaden the discussion about the consequences of not addressing the gender gap in Wikipedia, and we provide some research topics that can support the generation of recommendations and guidelines for a community that needs both equity and diversity.