Variable is very useful for these cases:

1. Request in multiple environment.

2. Request has many dynamic parameters in url query or body.

3. A request depend on one or more requests.

4. Need change request's url/headers/body before sending it.

Variable is always a key-value object and use with a uniform format: {{key}}, you can use variable in Common Pre Request Script, Pre Request Script, Test, Url, Body and Header.

All {{key}} will be replace to Value of the variable before or after sending reqeust. Variable transfer workflow reference to: Variable Transfer Workflow.

Hitchhiker have three types of variable.

1. Environment variable

2. Parameter variable

3. Runtime variable