The end product of transcription is an RNA transcript. This could be any form of RNA such as mRNA (messenger RNA), rRNA (ribosomal RNA), tRNA (transfer RNA), or non-coding RNA. Prokaryotes form a polycistronic mRNA whereas eukaryotes form a monocistronic mRNA. Transcription is catalyzed by the enzyme RNA polymerase. In prokaryotes, all three types of RNA are produced by a single RNA polymerase. In eukaryotes, transcription is catalyzed by three different types of RNA polymerase and each one forms a different type of RNA: 

1. RNA polymerase 1 produces rRNA, a component of a ribosome that facilitates translation 
2. RNA polymerase 2 produces mRNA, which is responsible for carrying genetic information from the nucleus to the cytoplasm
3. RNA polymerase 3 produces tRNA, which carries the corresponding amino acid to the ribosomes during translation