What is the function of DNA polymerase?

DNA polymerase is the enzyme that builds new DNA strands during DNA replication.

Here’s its function simply:

• It adds new nucleotides (A, T, G, and C) to the growing DNA strand.
• It uses the original DNA strand as a template to make a matching (complementary) strand.
• It works only in the 5′ to 3′ direction.
• It also checks for mistakes and corrects them — this is called proofreading.

In short:
DNA polymerase makes new DNA and ensures it’s copied correctly.