Yes, the bacterial operator is a binding site. It is mostly located in the region next to promoter.
The operator is the site of initiation, where the repressor binds. The binding of the repressor is through interactions between the DNA (deoxyribonucleic acid) sequence and the repressor protein.
When the operator is free, RNA (ribonucleic acid) polymerase will be able to transcribe proteins, but when the repressor binds to operator, RNA polymerase will not be able to proceed with gene transcription. Hence, the transcription process is inhibited.
If we see downstream, promoter comes first and then operator and then operon genes. The regulatory genes control the operator, which is situated upstream to the location of promoter.
The operon consists of an operator region and the three structural genes, which code for proteins.
The repressor in lac operon consists of four polypeptides. They attach to 24 base pairs region of the lac operator.
The repressor contains another part, which binds to allolactose. If allolactose binds with the repressor, the shape of the molecule will be changed. Then it cannot bind to the operator region; therefore, transcription cannot be inhibited.