Potable Document Format, or PDF, is one of the most popular document formats available. It is used for publishing and printing purposes. It is also used for web transfer of files. The main reason this format is preferred is due to its small size compared to other document formats. It stores the data in the form of images hence it occupies less amount of space. Even though the space utilization of this format is low, sometimes very large amount of data is stored leading to files of large size. This leads to the need for PDF compression.
Compression is a technique by which the data is encoded and made smaller in size. This encoded data can be sent to the receiver. The receiver decodes the data to get the original data back. The compression mainly works by removing unnecessary data and redundancy. One of the primary methods of compression is by removing continuous blocks of spaces by newline. This will lead to reduction in half the original size. The compression may be lossy or lossless. Lossless compression does not result in loss of data during compression. This method however has a limit for the compression ratio. Lossy techniques result in high compression ratio, but results in loss of data as well.
PDF compression softwares are available on the internet. There are free online PDF compression softwares available. These are available as free downloads and they have to be installed in the user system. Large number of free online PDF compression softwares have good compression ratios. Some commercial PDF compression softwares also offers free online PDF compression softwares as trial software. These softwares help in the user getting a feel of the product before purchasing it. The user may opt for free online PDF compression software for conversion of limited files. These may not give very good compression ratios but are suitable for limited usage. The free online PDF compression softwares are also available as plug in to your document reader. The usage of PDF as file format is increasing gradually and the need for PDF compression tools also increases. Free online PDF compression softwares are a cost effective alternative to commercial softwares