Introduction to Data Compression


Data compression in the technique of storing the data in such a way that it requires the less space than usual.   Compress is being performed by a special encoding scheme.  It is used to shrink the large files into smaller size in order to transfer them over the networks, intranet and the Internet. This technique is very useful in the data communications because it allows the network devices to transmit the same amount of data in the less bytes.  
 
It involves the different algorithms that make the repetitive bits unnecessary and thus make the data compressed. It has been widely used in the database management, backup utilities and the spreadsheets.  Certain types of the data files such as bit-mapped graphics, .gif, .doc, .mpg, .txt, .wav, and .avi file extensions. 

Sender and the receivers should understand the encoding mechanisms in order to make the data compression work effectively.  Compressions let you save your expensive resources such as the hard disk space, communication bandwidth and the communication time.  Compressed data must be decompressed in order to use it.  

Compression can also be performed on the audio and the video files but it requires additional hardware and software to decompress the audio and video data.  Following are the two major techniques of the data compression.

Lossless

In the lossless compression technique, the restored data is identical to the original.  This technique is must the data types such as word processing files, executable code, numerical values and the database entries.  In this technique a single misspelled word or numerical value is not affordable.

Lossy

In the Lossy technique, the compression allows some sort of degradation and noise. In this technique, the data files do not kept in the perfect condition for the storage.  The transmissions in the lossy technique contain the certain amount of noise. 

The higher compression rate adds more noise to the data.
By default Windows allow you to covert the files and folders if these are formatted with the NTFS file systems.  There are many third party software that let your files, folders, audio, video and images compress into smaller sizes. The most common compression software are WinZip and WinRar. 

Files that are compressed with these tools have extensions .zip and .rar.  These files can be decompressed by using the same tools at the other end.  The files that are very large even after compressing can be divided into smaller pieces and these pieces of the same files can be reunited at the other end. 

Most of the compression software can support multiple data types like .doc, .pdf, .wav, .mpeg, .jpg, .avi, .gif and others.