"Information technology (IT), as defined by the Information Technology Association of America (ITAA), is "the study, design, development, implementation, support or management of computer-based information systems, particularly software applications and computer hardware." IT deals with the use of electronic computers and computer software to convert, store, protect, process, transmit, and securely retrieve information." -- Source Wikipedia
Technology to process and communicate information .. information about goods, people, machine, location, photos, music ..lots lots type of information .. Process it and communicate it .. Its like a Black box for Non-IT person .. and that is how it should be.. (Our Jobs will be safe :) )
People like Kishore Biyani (Owner of future group, Big Bazaar) had the vision to sell goods at low price in a decent Mall-way .. He might not have any idea on which Operating system his Data server runs ..and what is the hardware configuration in his data center .. what front end is used to build BigBazaar web portal ..
All he has is an input requirement (Name of goods, Prices, Name of people, Their salary data, His office locations, His and His employees mails, Online sales portal details, Bank transactions etc ..) and He wants this to be processed by a black box called "Information Technology" and the output should be properly managed data in clear usable front end .. This formula is true for any other industry say Health care, Aviation, Government, Media, Banks, They all need IT as an API (Application Programmable Interface) so that they can call those APIs in their actual application (Not the software application but the business process application).
But there is a whole new world out there inside IT. there is Hardwares like Desktop, Laptop, Servers, Mobiles, PDAs, Routers, Network cable etc .. and there are software .like Operating system .. Application servers .. Web server .. Office suite .. Games .. Mobile softwares ..
Lets start with Hardware.. There are Hardware assembling vendors like IBM, HP, Dell which gets different parts from other vendors ..Processor from Intel/AMD.. Hard Disk from Seagate/Wetern Digital/Gigabyte .. RAM from Kingston Motherboard from Asus/Intel . Box from Asus etc ..
These processor vendors how they make Processors .. They get FPGA/CPLD/ASIC chips from Semiconductor vendors like Xilinx.. How these semiconductor vendor makes these chips and verifies that it works fine .. They use VHDL/VLSI/verilog simulator, Programmer, Tester tools like Modelsim..etc .. Then there are Embedded systems vendors .. Which makes small chips like RAM, NIC card.. Other Programmable chips, Timers, controllers ..
And how does these VHDL/Verilog code works when placed in FPGA chips. is there a magic..If Assembly language MOV A,20 (some 000111111100011110101111) said to it, It stores variable 20 in General purpose register .. and where is this register .. How can something gets stored (? magic or what) does that have mind.. There are flip-flops .and there are OR/AND/NOT gates .. Logical gates .. In essence which makes Mathematical instructions working ..and how this OR/AND gate works .. with signal . Digital signal ..010101 .. Off-On Off-On .. The clock .. If this clock stops .. Whole IT world is gone .. everything works around this clock .. (This is similar to Heart considering human as IT system..which keeps tick-tock-tick-tock every time.. Though one difference is there between a System and Human is, If System breaks down, that can be repaired but Human body ... ) Aha .and how come this tick tock happens tirelessly without stopping for years .. Whats that ..Its quartz crystal .. The valance electrons (? Now this is getting very very low and confusing ...) are moving and with a slight energy given to this electron, it changes its orbit ..
Similarly, How does I connect a RJ45 cable to this small NIC card (and with wireless, Bluetooth, Infrared, RF, Satelites, Even a cable is not required) and my friend gets the mail .. What is that connects between My computer in GM Palya, Bangalore to my friends Laptop in Andheri, Mumbai.. and it takes seconds to reach there.. Wow !! How does this happen .. everything goes over wire ..and what is there inside wire .. the current -- yes the analog current .. i.e flow of electrons .. What exactly (very very briefly), My mail client formed a SMTP packet with the mail content typed by me, along with my friends email address (@friend.com) and sent to the TCP layer ( a program in the OS) and here my TCP added the port number 25 for remote server, and some port local to have syn/Ack/Syn-ACK with My Mail server.. Puts these info into the packet ..and send to Network layer program implementation, which adds the IP address of Remote and local machines .. and send to Physical layer where .. Some checksum parity bits, MAC addresses etc were put in a big packet and then splitted into small packets and give to NIC card.. NIC card converts this Digital information to Analog signal using DAC .. This packet reaches to Airtel (My Internet service provider) and there he knows where to go from there ..ya Some router will use some algorithm (Protocol ..right ) RIP/OSPF/BGP to decide upon the route .. at my Mail servers Firewall, It will be checked for Viruses .. Strip down packet ..Send to Physical layer ..Network, TCP, SMTP and there it gets some processing and then goes back to My Friends mail server .. and after a refresh in my friends browser his Browser connects again to his mail server and find new mail in the server and fetches them .. As this is just a draft copy .. I have messed up so many things above .I have missed so many things ..(I need to learn end-to-end so that I have strings attached from my machine's mail to My friend's Machine and every logical question should have an answer).
More Info on email
So many things happen just to send a email .. What does Kishore Biyani will know about all these .. Kishore Sir, No need for you to know ..we are here no.. We will keep on learning, doing research on these to make it more easier for u to check ur mails and send Notes to ur employees .. U don't worry .. We are here to serve you ..
Many Many things ..Database .. Authentication, Authorization . Directory .. Productivity softwares, WinZip.. FTP/NFS.. Time servers .. Windows ..Linux .. Sparc .. Intel .. Z-series .. Development .. testing .. Management .. support .. Java .Net .. Oracle ..MS SQL .. JSP ..Telecom ..web application .n-tier .. Security .. People/Machines management . UI .. So many things are involved in IT .. I will keep on posting on this topic/thread.
We IT guys Rock . :)