Answer:
Digital white-out.
I am the only thing that place today before yesterday. (one word)
I am pronounced as one letter, written with three. I come in blue, black, brown, or grey. Reverse me and I read the same either way. What am I?
I am black and white. I have strings I have keys. I make sound without my lips. I make dough with no flour
I am clean when Iām black dirty when Iām white.
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.