Only TOEFL no GRE

Hi All,
I am a software engineer working in a firm.
In fact I want to appear for TOEFL for improving my English as per US English standards.
Is it necessary that for appearing TOEFL , one must through GRE?
If not , how would it be if I take TOEFL without GRE ? How difficult will it be , if I appear for TOEFL without GRE? Will TOFEL require more vocab than GRE or GRE vocabs come helpfull in TOEFL…or such kind of hurdles I will have to pass torough?

Looking forward for reply.

thanks
Aniruddha

TOEFL listening discussions: A conversation between two university professors

.
Hello, Aniruddha.

You can take the TOEFL test without taking the GRE. TOEFL is used as a measure of English ability of non-native speakers for entrance into 1st year university; GRE is for entrance into graduate school (5th year university) and is designed for native speakers. The GRE is much more difficult than TOEFL.