Using 'No' and related words
Spanish can require the use of the double negative under some circumstances. 
As part of a double negative: 
One aspect of Spanish that may seem unusual to Spanish speakers is the use of the double negative.
 If one of the negative words, such as nada or nadie is used after the verb, a negative (often no) also must be used before the verb. 
Such a usage is not considered redundant. 
As a general rule, if a Spanish verb is followed by a negative, it must also be preceded by no or another negative.
No conoce a nadie.  He doesn't know anyone.
No fui a ninguna parte.  I didn't go anywhere.
No sé nada.  I don't know anything, or I know nothing. 
A nadie le importa nada.  Nothing matters to anybody.
No debe saberlo nadie/ ninguno. Nobody has to know it.
It is possible to have one, two or three negatives in a sentence.
in Spanish  in many cases, use of double negatives is required. Even triple negatives are possible and common. 
sometimes the second negative is used to make a stronger statement, is used to add emphasis: 
No tengo ninguno. I don't have any. 
Nadie sabe eso. Nobody knows that.
Jamás fumo. I never smoke.
Tampoco comió. She didn't eat either.
Tampoco comió nada. She didn't eat anything either.
No habló. He didn't speak.
No dijo nada. He said nothing.
No le dijo nada a nadie. He didn't say anything to anybody.
No compro ninguno. I'm not buying any.
Nunca le compra nada a nadie. She never buys anything for anybody.
No come ni siquiera pan. He doesn't even eat bread.
Ni siquiera come pan. He doesn't even eat bread.

The most common negative terms in addition to NO are Most of these terms in Spanish have a corresponding affirmative term:
apenas  barely, scarcely, hardly algo something
jamás never siempre always
nadie nobody, no one alguien/todos somebody/ everybody
ni neither, not, nor  
ninguno none, no alguno/ todos some/ all
ni siquiera not even siquiera at least
nunca never siempre always
tampoco not even, nor, neither también also
nada nothing todo all

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