What's the significance of the Philadelphi corridor?

One of the main reasons the latest ceasefire talks failed is the Israeli insistence on keeping their forces in the Philadelphi Corridor. The Philadelphi Corridor is highly important for the passage of humanitarian and essential needs for Gaza as it is what divides Gaza from Egypt. The seizure of the Philadelphi Corridor further expands the excruciating toll of the Israeli blockade in Gaza which has greatly exacerbated the humanitarian crisis in the Strip.