This one is for the nontechnical people out there who have to deal with technical people in their work. At least some of you might have faced tough times when your tech counterparts start to talk about API. Well, don't worry anymore. I can assure you that APIs won't freak you out after going through these slides.

1. Don’t Let
API
Freak
You Out
Explaining API as
simple as I could
- Nithin Balachandran

2. An application programming interface (API) is a computing
interface which defines interactions between multiple
software intermediaries. It defines the kinds of calls or
requests that can be made, how to make them, the data
formats that should be used, the conventions to follow,
etc. It can also provide extension mechanisms so that
users can extend existing functionality in various ways and
to varying degrees. An API can be entirely custom, specific
to a component, or it can be designed based on an
industry standard to ensure interoperability. Through
information hiding, APIs enable modular programming,
which allows users to use the interface independently of
the implementation.
NOT HELPING A LAYMAN

3. Application Program Interphase
Program - Backend
Application – Front End
API
Call
Data
Response
User
Request
Data
Request
API
Response
Output
Action
How a Tech Guy Understand API

4. Bank Procedures
Bank Locker
Bank Customer Care Desk & Cash Counter
KYC verification,
Gold Verification etc.
Amount, Payee Account
details etc.
Customer Request To
Gold Loan
Authenticate to Open
Locker and keep the Gold
Pay slip to
cashier
Cash In Hand or In Account
To Customer
A Daily Life Analogy For A Layman
Just Imagine that you are visiting a bank for availing a bank service
– let’s say a Gold Loan.
Now reimagine the diagram that you saw before in the below way.

5. Simply Said,
APIs allows users to
communicate with software
easily and seamlessly
APIs just allow different
applications to communicate with
one another

6. API Terminologies
#1 PROTOCOL
Protocol is a set of rules defining how components can interact with each
other. Both parties must understand and uphold the same protocol for the
communication to be successful.
In our bank analogy, the bank staff and the customer should have a common
language
for understanding the customer’s need.
Also, just like a bank staff, an API is also limited to a very finite purpose.
You cannot go to a busy Bank and ask the staff to book movie tickets for you.
Can You?

7. API Terminologies
#2 Format
Format specifies how you can encode the data you want to send over between
the different layers of software.
Example : XML, JSON etc.
In our bank analogy, the format would be the standard gold loan request form
, KYC update request form etc. All financial institutions under the Central
Bank’s governance will have such formats almost universal.

8. API Terminologies
#2 API Endpoint
API Endpoint refers to a service provider that provides a specific subset of
functions within the same Interface. In this case, Tom and Sally are both
endpoints. Different endpoints can have different protocols and different
formats.
In our bank analogy, we might have different staffs employed at the customer
care desk for handling customer requests like the below
• Gold Loan Staff
• Vehicle Loan Staff
• Credit Card Staff
So on and so forth. These staffs are dedicated and trained to handle specific ,
differentiated customer requests that may come into the bank on a day.

9. What Is an API Error
API error can mean one of two things
• Something was so wrong in your
request or your application that
the API simply couldn’t
understand the request
• The API itself has many problems
that it cannot process the request
properly or it is serving back the
wrong data as response

10. What Else Can API DO
• APIs can have verification logic built into it to ensure
all operations are legal
• APIs can have error reporting mechanisms to
indicate an error has occurred
• APIs can determine pagination and navigation
• APIs can filter data and serve different subsets of
data based on need
• APIs can authenticate validity for security purposes

11. Thank you
“Tech Thoughts “
An attempt to demystify Tech
jargons & Buzz words