Help to identify old flooring
After I removed the carpet in the bathroom, what I found is a thin layer of this kind of flooring (see the image). The house was build in 1969, and I want to install vinyl tiles (would certainly prefer ceramic flooring; but I have done done flooring in my life).
What is this stuff? Can I keep it and lay tiles on it? If not, Is it safe to remove it myself? I have young children, and any hazard involved? See the other picture for detailed look of the edge. Thanks so much.