Without sounding too lazy here, is it necessary to peel fresh ginger and turmeric before you grate them and add them into a dish?

I guess not, but their grated skins float on top of a dish. I have never tried to grind it whole, which may solve this problem. To me, their skins seem a bit like husk, if that makes any sense, almost like onion & garlic skin, not for eating! Let's see what others think.

Mamta

I only cut off the really manky looking skins, else I don't bother, but I do chop my ginger very finely (usually). I never skin potatoes or other veg except some root veg, like swede.

Turmeric and galangal, like ginger, are rhizomes and so only have tough skins if old (last years crop). Also, at this time of year, watch out for frost damaged ginger, it looks dull and damp, and cannot be used, it rots easily.

I've never really thought about it, just following recipes that usually say 'peeled and grated' for ginger and I thought it was "the done thing!"

A Chinese friend laughed at me however seeing me peeling ginger -as long as it is reasonably fresh it is actually much easier, quicker (and economical) just to scrape most of the skin off with the tip of a spoon and solves the problem of all the nobbley bits.