Differences between Workflow, Flow and Process Builder in Salesforce?

Salesforce offers various tools to automate business processes using Workflow Rule, Flow and Process Builder.

Below is the main Differences between Workflow, Flow and Process Builder in Salesforce:

Items#	Workflow	Flow	Process Builder
Visual designer	Not available	Available	Available
Starts when	A record is created or edited	The user clicks on a custom button/link A Process starts Apex is called Inline Visualforce page The user accesses a custom tab	A record is created or edited
Supports time-based actions?	Yes	Yes	Supported, but only one scheduled-actions per criteria. This means that in the same Process.