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This example is for Wiring version 0024+. If you have a previous version, use the examples included with your software. If you see any errors or have comments, please let us know.

Iteration.
Iteration with a "for" structure constructs repetitive structures.

    void setup() {
      Serial.begin(9600);
      for(int i = 0; i<100; i++) {  // prints numbers from 0 to 99
        Serial.print(i);
        Serial.print(" ");
      }

      for(char c = 'A'; c<='z'; c++) {  // prints all characters between 'A' and 'z'
        Serial.print(c);
        Serial.print(" ");
      }

    }

    void loop() {

    }