Exact 
statement of the particular 
needs to be satisfied, or essential
characteristics that a 
customer requires (in a good, 
material, 
method, 
process,
service, 
system, or 
work) and which a 
vendor must deliver. Specifications are written usually in a manner that enables both 
parties (and/or an 
independentcertifier) to 
measure the 
degree of 
conformance. They are, however, not the same as 
control limits (which allow 
fluctuations within a 
range), and conformance to them does not necessarily mean 
quality (which is a predictable degree of 
dependability and 
uniformity). Specifications are divided generally into two main categories: (1) 
Performance specifications: conform to known
customer requirements such as keeping a room's 
temperature within a ...