Intron represents the opposite of exon. The DNA sequence that defines a gene, includes some pieces that are part of the final information line-up and other pieces that are not. The useful pieces are called executed regions (exons) and the left out sections are celled intragenic regions (introns). An intragenic region means that it is located within the gene sequence, but is not actually part of it. The introns are physically snipped out of the sequence to leave only the exons which are then spliced back together.

This whole process seems amazingly elaborate. Sometimes the process is connected to the phenomenon of alternative splicing. Such elaborate processes in cell biology clearly reveal purpose and planning to make it work. Can you imagine a blind process that could achieve all this in the cell?