In science fiction movies and shows like "The Martian" or "For All Mankind", Mars is often depicted as a challenging but ultimately survivable environment for humanity. Though conditions might be difficult, with enough rugged ingenuity and perseverance, mankind is able conquer the Red Planet in these stories in the ways we have the frontiers of Earth.
The reality is a very different story. Exposure to the unmediated Martian environment isn't just hostile to human beings; it's immediately lethal. While it may be possible to create a habitable environment on Mars, those habitats would be closer to hermetically sealed space stations or submarines than frontier settlements.
