Digital signature certificates (DSC) provide a digital equivalent of a physical signature and can verify identity online. There are two main types of DSC in India - Class 2 for individuals and Class 3 for organizations requiring higher assurance. The government assures five companies can provide DSCs across India, like TCS and ACE Technology in Rajasthan. DSCs allow vendors, bidders, and others to electronically sign and submit documents from anywhere, reducing paperwork. The goal is to make government services more accessible online through programs like MCA21.