Does drywall always have to be taped & mudded?

I had to open the bathroom wall from the backside because I had to redo the plumbing for the sink and it was a galvanized pipe so I cut it and replaced it with ABS but the ABS pipe was 1 1/2 inch so I had to make a bigger hole in the wall and the only I succeeded was using a chisel and a hammer and punched out a bigger hole. I notice there is metal mesh and maybe cement or plaster maybe and the tile is on top of that. I notice where there is no tile, the wall is drywall but everywhere there is tile around the bathroom I assume the walls are all like this: Front of wall: [ATTACH]49087[/ATTACH] Behind wall: [ATTACH]49088[/ATTACH] [ATTACH]49089[/ATTACH] The house was built in 1961 and I am wondering what kind of walls are they? Is that the way they used to lay tile back in the day? I assume drywall existed back then because the untiled portion of the wall is drywall so I guess they didn't lay tile on top of drywall back then?

In our house we just purchased, it has this texture in the ceiling of 4 bedrooms and the livingroom and dining room. We tried the technique for scraping like you would with a popcorn ceiling of wetting it and then using a scraper we got at Home Depot meant just for this purpose. However, this texture on our ceiling does NOT want to cooperate. We are able to knock down the peaks some with serious scraping but can't get it anywhere near smooth. So, I'm looking for other options. Better ways of scraping or sanding to remove it. Right now, our plan is to scrape, then sand, then skimcoat to make it flat. We just finished sanding one bedroom but it's brutal with the sander I have. It's electric but it weighs probably 5+ pounds. So, holding that overhead for more than a minute or so while sanding gets to be a lot. It's SLOW going. Any advice you can provide is GREATLY appreciated! Here is a picture of what I'm up against: [ATTACH]49400[/ATTACH]