Hot Backup and a Cold Backup

Cold Backup- We can take the Backup while DB(eg. Oracle) is down. 
Hot Backup-We can take the Backup while DB(eg. Oracle) is running. 

Cold backup is a physical backup. During a cold backup the database is closed and not available to users. All files of the database are copied (image copy). The datafiles do not change during the copy so the database is in sync upon restore. 
Used when: Service level allows for some down time for backup 


Hot backup is a physical backup. In a hot backup the database remains open and available to users. All files of the database are copied (image copy). There may be changes to the database as the copy is made and so all log files of changes being made during the backup must be saved too. Upon a restore, the changes in the log files are reapplied to bring the database in sync. Used when:A full backup of a database is needed Service level allows no down time for the backup

Package and Language?

Package:

It is a well defined program used to manipulate the data. Eg. Ms- Office

Language:

Using language we can create package as well as other application programs.

Eg. Java, C++...

Computer Organization and Computer Architecture

Computer Organization is how operational attributes are linked together and contribute to realise the architectural specifications.
Computer architecture is the architectural attrributes like physical address memory,CPU and how they should be made and made to coordinate with each other keeping the future demands and goals in mind.
Computer Architecture comes before computer organiation.Its like building the design and architecture of house takes maximum time and then organisation is building house by bricks or by latest technology keeping the basic layout and architecture of house in mind.  

DBMS and Data warehouse

A DBMS is a Database management System, it consists of the tools needed to access or build a database. A Data Warehouse is merely a collection of data from one or more sources collected together to enhance the the activities of data mining, which is performed with a DBMS or a RDBMS*.

Information Systems and Information Technology?

Information Systems is a large umbrella referring to systems designed to create, store, manipulate, or disseminate information. Example of an information system is a pencil and a piece of paper. The two objects themselves are just tools, but together they create a system for writing (information). The term Information systems has been around a lot longer than the computer, or the term information technology. These days the two are sometimes thought to be synonymous, but that, in most cases is a misconception. 

Information technology falls under the information systems umbrella, but has nothing to do with systems per say. IT deals with the technology involved in the systems themselves, e.g. an information system like wiki.answers.com contains many information technologies. Servers, server operating systems, web-server software (IIS, Apache, et al), and code written for the web-server software (PHP, C#, VB, PERL, Ruby, et al). Even your computer and browser make up part of this information system. Like the pencil and paper example, each one of the mentioned parts of this information system in itself is an information technology. 

That being said, most people in the profession no longer make a distinction. Moreover, companies call their IS/IT department a wide range of titles based on more on culture and tradition than anything else.