Cloud computing is fastest growing internet technology nowadays. It can be enable on demand network access to a shared pool of configurable resources. The virtualization is a core part of cloud computing which enables physical resources to partition into virtual resources so that they can be shared among individual virtual machines. While using this virtualized resource can be reduce wastage of storage, server and physical machines. The virtualization techniques consist of hardware, hypervisor and virtual machine monitor (VMM). It enables intellectual IT resources on demand dynamic allocation of resources such as network, storage, application, server and client. This hypervisor becomes significant as a way to develop system security, provide greater flexibility, scalability and reliability. In recent years, there is an increased desire to use virtualized systems in enterprise mainly focused on in order to reduce cost and more efficiently utilize resources. This paper describes different types of hypervisor and virtualization techniques, how it helps to expand the elasticity of the resources in cloud computing environment.