M24 and M64

Hello, we got our hands on a hand-me-down Hardinge Elite 8/51. It's in extremely good shape, so this is a good thing.

However, I was looking through the programs that were on there, and they consistently use a M24 and M64 after every tool change, no matter what type of tool it is.

I've always programmed Haas lathes, and I've never had to use these before.

Does anyone know why they would have these in there after every tool change?

All help is appreciated.

M24, Main spindle contouring mode off
M64, Spindle feedback from main spindle

M24, Main spindle contouring mode off
M64, Spindle feedback from main spindle