As the term indicate DNA it is more likely like a DNA but cDNA is a complementary DNA that synathesized from a single-stranded RNA in a reaction of the enzymes. The clone eukaryotic genes in prokaryotes is used by the term of cDNA. The cDNA can be stored overnight at 4˚C or -20˚C and the enzyme which called reverse transcripted cDNA sequence from the RNA fragement. This creates the hybrid molecules which are the combination of cDNA and RNA.
To test the cDNA use a small aliquot in cDNA and PCR amplify beta actin and it implies that the cDNA is good but be sure to add water only neg control and to run cDNA on a gel is the way to confirm cDNA synthesis most cDNA copy the only RNA in the roughly ratio of 1:1.