What's Up With My Plastic-ish Walls? -- Good Questions

Pin it Q: I'm a Southern transplant to the (currently freezing, brrr!) heart of the Midwest. I live in a 99-year-old building. I love its quirky layout, the boiler heat, the updated electrical and windows, and the convenient location to my grad student office and classes. What I don't love are the walls (well, and the gawd-awful kitchen, but that's another story...). I know that the walls are plaster, but they are textured with some kind of plastic coating [photo below]. It is definitely plastic...