• stratum
  Stratum
  In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers...
  
  , the basic unit of lithologic stratigraphy
  Stratigraphy
  Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....
  
  .
• stratum or strate, a language
  Language
  Language may refer either to the specifically human capacity for acquiring and using complex systems of communication, or to a specific instance of such a system of complex communication...
  
   influencing or influenced through contact
  Language contact
  Language contact occurs when two or more languages or varieties interact. The study of language contact is called contact linguistics.Multilingualism has likely been common throughout much of human history, and today most people in the world are multilingual...
  
  .
• Stratum, Netherlands, a city district of Eindhoven.
• Stratum (statistics)
  Stratified sampling
  In statistics, stratified sampling is a method of sampling from a population.In statistical surveys, when subpopulations within an overall population vary, it is advantageous to sample each subpopulation independently. Stratification is the process of dividing members of the population into...
  
  , a homogeneous subgroup of members in the (sample/full) population

Telecoms

• In carrier telecommunications systems, stratum is used to describe the quality of a clock used for synchronization
  Synchronization in telecommunications
  Many services running on modern digital telecommunications networks require accurate synchronization for correct operation. For example, if switches do not operate with the same clock rates, then slips will occur and degrade performance...
  
  .
• The term stratum is also used to define the levels in the hierarchy of clocks defined by the Network Time Protocol
  Network Time Protocol
  The Network Time Protocol is a protocol and software implementation for synchronizing the clocks of computer systems over packet-switched, variable-latency data networks. Originally designed by David L...
  
   and Precision Time Protocol
  Precision Time Protocol
  The Precision Time Protocol is a protocol used to synchronize clocks throughout a computer network. On a local area network it achieves clock accuracy in the sub-microsecond range, making it suitable for measurement and control systems....
  
  .

See also

• For titles of artistic works and other uses almost always in the plural, see strata (disambiguation)
  Strata (disambiguation)
  Strata is the plural of stratum ; for other uses in which it can be used in the singular or plural, see Stratum .Strata may refer to:* Strata , 1990...
  
  
• Stratification (disambiguation)
• Substrate (disambiguation)
• Superstrate