what is "Array out of range" error?

 
i've got this error "Array out of range", what is it?
Documentation on MQL5: MQL5 programs / Runtime Errors
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MQL5 programs / Runtime Errors - Documentation on MQL5
 

For example, you have array with ten elements where their indexes are from 0 to 9

double array[10];

and you try to access to array[-1] or array[10].

Reason: