请问上下文是什么背景的呢？
footprint有很多意思，包括品牌印迹、碳足迹、企业占用空间等……

we describe two cases that we believe fit the pattern of “footprint competition” based on superior architectural knowledge. The first case involves Sun Microsystems and Apollo Computer in the late 1980s. Here we have information on how Sun used architectural knowledge to achieve a smaller footprint, and thus we can tie Sun’s invested capital advantage to specific architectural innovations. The second case involves the competition between Dell and Compaq (and other PC makers) in the late 1990s.

这是语境，结合这语境，请问这里footprint如何解释？