What is the difference between a signature stamp and an electronic signature?

The ESIGN Act is lacking in clarifying what distinguishes an e-stamp from an electronic signature. However, it is widely thought that stamps are more trusted by businesses and legal entities. The legislation holds that both an eSignature and an E-stamp must fulfil almost identical criteria, yet this differs to digital signatures which necessitate private, validated keys and can be seen as more complex to set up and manage.