IT Interview Questions and Answers 2019: March 2019

Thursday, 21 March 2019

Top 26 Hardware and Networking Interview Questions and Answers 2019 [updated]

1. Mention different Types of Operating Systems

Microsoft Windows, Linux, IOS, MAC, Unix

2. Mention microsoft client and server Operating Systems

Microsoft Client Operating Systems
Windows 95, Windows 98, Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10

3. Microsoft Server Operating Systems

Windows Server 2000, Windows Server 2003, Windows Server 2008, Windows Server 2012, Windows Server 2016

4. How will you check whether the SMPS is working or not?

Use a small copper wire and short the Green and Black wires.Give the power input to the SMPS,if the SMPS fan rotates then the SMPS is working otherwise not.

5. What are the Input and Output voltage of SMPS?

Input voltage:
230 volt AC current
Output voltage:
+5 v,-5 v,+12 v,-12 v,+3.3 v,-3.3 v and Ground

6. What are the types of SMPS connectors

Power Connector, Molex Connector, Mini Connector, Sub mini Connector, Sata Connector

7. What are the types of Hard Disk

IDE Hard Disk,SATA Hard Disk, SCSI Hard Disk

8. What are the Types of Partition?

Primary Partition,Extended Partition,Logical Drive

9. What are the types of RAM?

SRAM, DRAM, SDRAM, DDR1, DDR2, DDR3, DDR4

10. How can we differentiate the various types of RAM?

We can differentiate based on notches, no of pins,data transfer Speed

11. What is POST and BIOS?

POST stands for Power On Self Test.It is the process by which the computer checks whether all devices’ connection and power supply is proper.POST happens during startup.

BIOS Stands for Basic Input Output System.It maintains all hardware information.

Whatare the layers of the OSI reference model?

There are 7 OSI layers: Physical Layer, Data Link Layer, Network Layer, Transport Layer, Session Layer, Presentation Layer and Application Layer.

13. What is a LAN?

LAN is short for Local Area Network. It refers to the connection between computers and other network devices that are located within a small physical location.

14. What are routers?

Routers can connect two or more network segments. These are intelligent network devices that store information in its routing table such as paths, hops and bottlenecks. With this info, they are able to determine the best path for data transfer. Routers operate at the OSI Network Layer.

15. What is subnet mask?

A subnet mask is combined with an IP address in order to identify two parts: the extended network address and the host address. Like an IP address, a subnet mask is made up of 32 bits.

16. What is NIC?

NIC is short for Network Interface Card. This is a peripheral card that is attached to a PC in order to connect to a network. Every NIC has its own MAC address that identifies the PC on the network.

17. How many layers are there under TCP/IP?

There are four layers: the Network Layer, Internet Layer, Transport Layer and Application Layer.

18. What is a private IP address?

Private IP addresses are assigned for use on intranets. These addresses are used for internal networks and are not routable on external public networks. These ensures that no conflicts are present among internal networks while at the same time the same range of private IP addresses are reusable for multiple intranets since they do not “see” each other.

19. What are MAC addresses?

MAC, or Media Access Control, uniquely identifies a device on the network. It is also known as physical address or Ethernet address. A MAC address is made up of 6-byte parts.

20. Describe star topology

Star topology consists of a central hub that connects to nodes. This is one of the easiest to setup and maintain.

21. What is the disadvantage of a star topology?

One major disadvantage of star topology is that once the central hub or switch get damaged, the entire network becomes unusable.

22. What is the difference between a hub and a switch?

A hub acts as a multiport repeater. However, as more and more devices connect to it, it would not be able to efficiently manage the volume of traffic that passes through it. A switch provides a better alternative that can improve the performance especially when high traffic volume is expected across all ports.

23. What is ipconfig?

Ipconfig is a utility program that is commonly used to identify the addresses information of a computer on a network. It can show the physical address as well as the IP address.

24. Describe networking.

Networking refers to the inter connection between computers and peripherals for data communication. Networking can be done using wired cabling or through wireless link.

25. What is one advantage of mesh topology?

In the event that one link fails, there will always be another available. Mesh topology is actually one of the most fault-tolerant network topology.

26. What are the full form of SATA, SCSI, FAT, NTFS, SMPS

SATA: Serial Advanced Technology Attachment

SCSI: Small Computer System Interface

FAT: File Allocation Table

NTFS: New Technology File System

SMPS: Switch Mode Power Supply

1.What is HTML?

HTML stands for Hyper Text Markup Language. It is used to create and display pages on the Web. It makes the text more interactive and dynamic.

2.What is Semantic HTML?

Semantic HTML is a coding style. It is the use of HTML markup to reinforce the semantics or meaning of the content.

For Example: In semantic HTML tag is not used for bold statement as well as tag is used for italic. Instead of these we use and tags.

3.What are Empty Elements?

HTML elements with no content are called empty elements. For Example:<br>, <hr> etc.

4.Does HTML Support Javascripts?

Yes, HTML supports JavaScripts. We can use JavaScript anywhere in the HTML Coding. Mainly there are four sections where we can add JavaScript in HTML.

1. Head Section : We can add JavaScript in Head section of HTML.<head>…..Javascript…. </head>

2. Body Section : <body>….. Javascript…</body>

3. Head and Body both : We can add Javascript in both head and body section. <body….Javascript…</body> and <head>…..Javascript…. </head>

4. External File : Script in and external file and then include in <head> ….. </head> section.

5.What is Difference Between HTML and HTML5?

Document of HTML is very large as compare to the HTML5.
Audio and Video tags are not present in HTML whereas HTML5 contains audio and video tags.
HTML supported by all old browsers whereas HTML5 is supported by new browser.

6.What is CSS?

CSS stands for Cascading Style Sheets.
It is used to design the Webpage.
CSS plays an important role in building the website.

7.How can you Integrate CSS on a Web Page?

There are three methods to integrate CSS on web pages.

Inline method– It is used to insert style sheets in HTML document
Embedded/Internal method– It is used to add a unique style to a single document
Linked/Imported/External method– It is used when you want to make changes on multiple pages.

8.Explain the Difference Between Visibility: Hidden and Display: none?

Visibility: Hidden hides the element, but it occupies space and affects the layout of the document.
Display: none also hides the element but not occupy space. It will not affect the layout of the document.

9.What is JavaScript?

JavaScript is a scripting language.

It is used for Validate the webpages.
It is object-based, lightweight, cross-platform translated language.
It is widely used for client-side validation.

10. What are the pop-up boxes available in JavaScript?

Alert Box
Confirm Box
Prompt Box

11.What is MySQL?

MySQL is an open source DBMS which is built, supported and distributed by MySQL AB (now acquired by Oracle)

12.What is the Difference Between Truncate and Delete?

Delete command is used to delete data from a table.

For Example : Remove emails where we write a script to delete the customer’s data. It deletes the rows of data from a table.

Whereas, Truncate is very dangerous command and should be used carefully as it deletes every row from a table.

13.What is PHP ?

PHP: Hypertext Preprocessor
It is open source server-side scripting language that is widely used for creation of dynamic web applications.
PHP is a loosely typed language

14.What is the Difference Between “echo” and “print” in PHP?

Echo can output one or more string but print can only output one string and always returns
Echo is faster than print because it does not return any value.

15.What is the Difference Between Include() Function and require() Function?

If there is any problem in loading a file then require() function generates a fatal error and halt the execution of the script.
include() function generates a warning but the script will continue execution.

16.What is session in PHP ?

PHP sessions are the simple way to store data for individual users/client against a unique session ID.

17.What is Default Session Time and Path in PHP?

Default session time in PHP is 1440 seconds (24 minutes) and Default session storage path is temporary folder/tmp on server.

18.What are Different Types of Errors Available in PHP ?

There are 4 types of errors in PHP, We have listed all below

E_ERROR: A fatal error that causes script termination.
E_WARNING: Run-time warning that does not cause script termination.
E_PARSE: Compile time parse error.
E_NOTICE: Run time notice caused due to error in code.

19.What does Isset() Function?

The isset() function checks if the variable is defined and not null.

20.What is the Difference Between GET and POST?

GET displays the submitted data as part of the URL, during POST this information is not shown as it’s encoded in the request.
GET can handle a maximum of 2048 characters, POST has no such restrictions.
Normally GET is used to retrieve data while POST to insert and update.

21.What are Different JOINS used in SQL?

There are 4 major types of joins made to use while working on multiple tables in SQL databases

Inner Join
Left Join (Left Outer Join)
Right Join (Right Outer Join)
Full Join (Full Outer Join)

22.What is Constraints? Mention its Types?

SQL constraints are used to specify rules for the data in a table. Constraints are commonly used in MYSQL.

Primary Key
Foreign Key
Unique Key
Check
Default
Not Null
Null
Index

IT Interview Questions and Answers 2019