A DNA polymerase that catalyzes the polymerization of DNA, using DNA, RNA or DNA:RNA hybrids and RNA templates. In addition to possessing 5′-3′ DNA polymerase activity, the enzyme also possesses some RNAase H activity, which cleaves RNA:DNA hybrids. It is mainly used for the synthesis of first and second strand cDNA and primer extensions. To a lesser extent, it is used for RNA sequencing and preparation of probes for hybridization.