The document discusses 10 common questions that may be asked in a Hadoop technical interview. It provides definitions for big data and the four V's of big data (volume, variety, veracity, velocity). It also discusses how businesses use big data analytics to increase revenue, examples of companies that use Hadoop, the difference between structured and unstructured data, the concepts that Hadoop works on (HDFS and MapReduce), core Hadoop components, hardware requirements for running Hadoop, common input formats, and some common Hadoop tools. Overall, the document outlines essential information about big data and Hadoop that may be helpful to review for a technical interview.

1. Preparingfor Hadoop interview? Here are a few predictable questions
Big Data has been attested as one of the fastest growing technologies of this decade and thus potent
enough to produce a large number of jobs. While enterprises across industrial stretch have started
building teams, Hadoop technical interview questions could vary from simple definitions to critical case
studies.Let’stake quickglimpseatthe mostobviousones.
1. Whatis Big Data?
Big Data refers to such gigantic set of data that has massive potential for mining, but cannot be
processed as such with traditional tools. However, any data cannot be classified as Big Data; only the set
that has high volume, veracity and velocity can be qualified as such. In order to draw meaning from such
data we need to utilize tools such as Hadoop. For that to happen, one needs to undergo a relevant
Training in Hadoop or any relatedsoftware tool.
2. Whatdo the four V’s of Big Data denote?
A fittingdefinitionhasbeenputforwardbyIBM:
1. Volume:Huge amountof data
2. Variety:A large varietyof data
3. Veracity:Datathat has inherentuncertainty
4. Velocity:Analysisof streamingdata
3. How Big Data analysis helpsbusinessesinincreasingtheirrevenue?
There are a lot of ways in which businesses can use Big Data analytics to their advantage. For instance,
Wal-Mart, the biggest retailer in the world, uses predictive analytics for launching new products on the
basis of customer needs and preferences. The who’s who of global businesses – Facebook, LinkedIn,
Twitter, Bank of America, and JP Morgan Chase and many more – use the same for boosting their
revenue. Businesses and professionals interested in utilization of the same can choose to learn Hadoop
– the mostpopulartoolsinthisregard.
4. Name some companiesthat use Hadoop?
1. Yahoo (the topcontributorwithmore than80 percentof itscode)
2. Netflix
3. Amazon

2. 4. Hulu
5. Spotify
6. Twitter
7. Amazon
5. Whatis structured and unstructureddata?
Structured data refers to such data that can be stored in traditional database systems in the form of
columns and rows. On the other hand, unstructured data refers to data that can be stored only partially
intraditional database systems.
6. On what concept the Hadoop framework works?
HDFS: Hadoop Distributed File System: This is a Java based file system for reliable storage of large
datasets
Hadoop MapReduce: This is Hadoop framework programming paradigm based on Java which provides
scalabilityacrossvariousHadoopclusters.
7. List the core componentsof Hadoop application
i) HadoopCommon
ii) HDFS
iii) HadoopMapReduce
iv) YARN
v) Data Storage – Pigand Hive
vi) Data serializationcomponents:ThriftandAvro
8. Whatis the bestHardware configurationto run Hadoop?
Dual core processor with 4GB or 8GB RAM, with ECC Memory. ECC memory is recommended as non ECC
memoryisnormallyassociatedwithconfigurationchecksumerrors.
9. Whatare various common inputformats?
i) Textinputformat– defaultinputformat
ii) Sequence fileformat
iii) Keyvalue inputformat
One can developadeepunderstandingof keyBigDataconceptsby optingfor Training in Hadoop
10. Name some Hadoop tools that are requiredfor workingon Big Data
A: Some such tools include Hive, HBase and Ambari and many more. Interested individuals should
choose to learnHadoop to getmore informationonthe same.

3. These were some of the most common yet important Hadoop technical interview questions. A high
level understandingof afewreal time case studiescouldhelpyousail through.