Differences between Salesforce Workflows and Process Builders

Anybody familiar with the older version of Salesforce which is Salesforce Classic will be familiar with a very useful feature of Salesforce called Workflows.
Process Builders came into picture much later, post Salesforce Lightning,replacing workflows with better performance and many more capabilities as compared to workflows.
Why Workflows or Process Builders when we can Code? The thumb rule of Salesforce is using declarative methods – i.e. Click before Code.  If a business we are unable to achieve to set up a business process by either using Workflow or a Process Builder, we then resort to coding. But first try to use declarative methods before attempting to code.
But first let us understand what workflows in Salesforce are and what functionalities they can do for the end-user:
Workflows are basically Automate business processes based on certain defined. For example, create a Big deal alert for the VP of Sales whenever the Opportunity amount is greater than 50,000 dollars. Here, we can easily create an Email Alert to be automatically sent to the VP of Sales if the Opportunity amount meets the criteria. Now let us understand what other automations can workflows do for us; Workflows help us in the following four main objectives as stated below:
Workflows CAN:

1. Create Email Alerts
2. Field Updates (Based on Business Criteria)
3. Create Outbound Messages (Meaning messages to be sent to an Non-Salesforce User or a User who does not exist in the Salesforce system)
4. Create Tasks (For Salesforce Users); Example A Task from the Manager to his subordinate to follow-up on a prospect with setting a due date with his comments.

How to Create a Workflow Rule
If you do not already have a Developer Edition, basically attesting environment for your own R&D, you can sign up and download it for free from https://developer.salesforce.com/signup which is free.
Once you have downloaded an developer edition for yourself and set a username and password, you are ready to get started.
To create workflow rules, click on Settings on the top right hand corner of your screen. On the left panel type Workflows and rules. Click on Workflow. The system will ask you to define a Workflow Rule name for your rule, give a name and be sure to write why you are creating this rule and what it does in the Description box before saving the name as it comes handy when you re-visit this rule and do not remember what this rule exactly does. The next step is to define the business criteria in the Business Criteria provided on the same page (You can define more than 5 Business criteria based on Zip code, Region, Amount etcetera based on your needs. At a given point of time only 5 lines of Business Criteria are visible on the page; If you need to add more criteria simply click on the ADD button).
Once the Business criteria is defined, select what action should the system perform based on the criteria i.e. send an email alert or create a task or send an outbound message or even update a field from any Salesforce object. Click save button and you are done!!  It’s that easy.
Though Workflows can perform automations, why do we need Process Builders? The older editions of Salesforce which have workflows implemented will continue to support workflows but his functionality will slowly be replaced by Process Builder which can perform far more automations and tasks as compared to workflows. First let us list out what actions can Process Builder Perform:

1. Create a Record
2. Update any related record (Not just a parent record)
3. Use a quick action to create a record
4. Send an email
5. Launch an Apex Flow
6. Post to Chatter
7. Submit for Approval automatically
8. Invoke a process defined
9. Call an Apex Code.

(Process Builder has one limitation though – It cannot send an Outbound message)
The process builder works like basic computer programming language.
There is a Start Button, select an Object on which you want to perform an action, Decision making (Defining Criteria) and finally based on Yes or No complete the objective of the operation. If we were to visualize a Process builder it would look similar to the flow chart below:



The Lightning Process Builder is a new workflow tool that helps you easily automate your business processes by providing a powerful and user-friendly visual representation of your process as you build it. Instead of doing this repetitive work manually, you can configure processes to do it automatically. The Process Builder’s simple and powerful design allows you to automate processes.
You can use the Process Builder to perform more actions than with workflow:
You can think of both Workflows and Process Builders as automation tools, but workflows is old school and has limited actions, whereas Process Builder can do much more than workflow as listed above.

Let us understand when to use workflow and when to use Process Builder:

1. Since you cannot send an outbound message using Process Builder use a Workflow.
2. If you have defined many business criteria and want to control the sequence of order in which the execution of tasks is performed use Process builder. With Process Builder you will be able to evaluate criteria of the business processes using process builder.
3. Salesforce Product Team will continue to enhance Process Builder features while slowly discontinuing support to Workflows. This means no more new features being added to Workflows in the future.

So what about those scenarios where both Workflows and Process Builders fail to be the solution for your Business problem? Then you go for C-O-D-I-N-G. But before Coding, remember the Thumb rule of Salesforce Click before Code, Declarative methods before coding.
If you are from the Salesforce Classic Era and are not yet confident to use Process Builders, Trailhead covers Process Builder with some hands on activity which you can practice in your Developer Org using multiple business scenarios until you are confident to use process builder in the Production Org of Salesforce.
I hope that you are now familiar with the differences between Workflows and Process Builders and their Functionalities. If you still need to read up more on these features from Salesforce and looking for some hands-on activity, I suggest using Trailhead which is a cool and Fun way of learning Salesforce.
Hope this article helps you differenciate between Workflows and Process Builders.