Difference between $state.transitionTo() and $state.go() in Angular ui-router

In AngularJS, I see sometimes we use $state.transitionTo() and sometimes we use $state.go(). Can anyone tell me how they differ and when one should be used over the other?

Are you referring to the AngularUI Router? If so, the wiki specifies the differences:

$state.go(to [, toParams] [, options])

Returns a Promise representing the state of the transition.

Convenience method for transitioning to a new state. $state.go calls $state.transitionTo internally but automatically sets options to { location: true, inherit: true, relative: $state.$current, notify: true }. This allows you to easily use an absolute or relative to path and specify only the parameters you'd like to update (while letting unspecified parameters inherit from the current state).

---

$state.transitionTo(to, toParams [, options])

Returns a Promise representing the state of the transition.

Low-level method for transitioning to a new state. $state.go() uses transitionTo internally. $state.go() is recommended in most situations.

$state.transitionTo transite to a new state. In most cases, you don't have to use it, you may prefer $state.go.

It takes some parameters in an options object:

• location: If true will update the url in the location bar, if false will not. If string "replace", will update url and also replace last history record.
• inherit: If true will inherit url parameters from current url.
• relative (stateObject, default null): When transitioning with relative path (e.g '^'), defines which state to be relative from.
• notify: If true, will broadcast $stateChangeStart and $stateChangeSuccess events.
• reload: If true will force transition even if the state or params have not changed, aka a reload of the same state.

$state.go is a sort of shortcut that call $state.transitionTo with default options:

• location: true
• inherit: true
• relative: $state.$current
• notify: true
• reload: false

It is more convenient as the synthax is simpler. You can call it only with a state name.

$state.go('home');