What is data abstraction in database management? Which stage of database design is it used in? How does it help the database developer during the design of a database? Name the different levels of data abstraction? What is the function of each level? What is classification and how is it used to build an abstract hierarchy?

When is a computer’s hard disks referred to as Just a Bunch of Disks? Differentiate between RAID and JBOD? Which one is a better option for storage and why? What is spanning technique used in JBOD? Why IS JBOD referred to as a risky option? What are the advantages of JBOD? 

Hashed and salted passwords are used in cryptography to reduce password vulnerability to hash attacks. What is the process of hashing? What is the process of salting? How do hashing and salting work to protect passwords from brute attacks? In this context, what is fingerprinting?

What does the acronym DHCP stand for? Describe how the DHCP works? What is the purpose of using DHCP? How does it help to eliminate manual intervention for keeping track of IP address? How does DHCP help to eliminate the issue of an IP conflict caused by a static IP address?

I read about Google's Project Tango which says Google is developing a tablet/smartphone focused on developers interested in 3D sensing and similar applications. Are there currently any other tablets which can be used for that purpose? Because apart from the memory and processor , a lot of tablets have similar specs so I wanted to try my hands on 3D sensing using existing hardware on the market. Any suggestions (tablets) ?

I am planning to buy the LG G3 . I have read a lot about the laser autofocus in the phone and I have a question regarding the battery life and video recording. Does the laser affect the battery life significantly ? Because I use the camera a lot, I would like to have a phone with a decent battery life. Also, can it help in recording video? Changing focus and such? What other purposes can it fulfil? 

So I'm planning to buy a smartwatch, namely the Asus ZenWatch. I have a question about the software. Is it "moddable" like other android devices? Are there custom ROMs for it ? It has those watch faces and stuff so are the big players like CyanogenMod working on making custom ROMs or faces or whatever for these watches? Also, are there any other useful apps or software to mod the watch? 

Regarding the much talked about "edged screen" on the Galaxy Note Edge, are all the useful and popular apps on play store compatible with the edge and its interface? Also, I root and install custom ROMs on all my smartphones and I love tinkering around with them. So I was wondering if all the popular custom ROMs like CM and all are compatible with the edge? Are they optimised to work with the edge?

I'm using Cygwin and Notepad++ on Windows 7 Ultimate to make C programs and I've just started learning C. I have a question about using the EOF operator in loops. For example if I use "  while (x!=EOF) " , what exactly is EOF ? How does the compiler know where does the file/input end? I always have to use Ctrl+Z to end my input or for EOF, how do I make EOF native to the input or file ?

I recently bought the HP 15 R022TX laptop online and it came with just DOS installed in it and I installed Windows 8.1 Pro on it. I'm facing some problems with the bluetooth and WLAN drivers. I cannot create an ad-hoc network without using the command prompt and the bluetooth device doesn't turn off and works erratically. How can I resolve this and is anyone else facing the same problems?