What is the matching of complementary nucleotide bases?

The nucleotide "A" base pairs with the nucleotide "T", Similarly, the nucleotide "C" base pairs with the nucleotide "G", and in the same way, The nucelotides "T" and "G" base pairs with nucleotides "A"and "C" respectively. The complementary nucleotide sequence is thus the base pair with which it forms a double-stranded structue of the DNA, for example the complementary sequence for "ACGTTTA" is "TGCAAAT".