The best type of paper shredder is the one that is suited to your particular needs. Cross-cut and micro-cut shredders (also known as nano-cut shredders) are designed for different types of shredding tasks, and selection depends on the shredding job at hand.
Here are some tips and general information about these two types of shredders.
1.  Cross-Cut
Cross-cut shredders are used for medium security tasks, and are not as secure as micro-cut shredders. In formal terms the security levels offered by cross-cut machines are known as levels P3 and P4.
These symbols refer to the width of the shredded strips, with P3 being the widest, and shredded strips becoming narrower as the P-factor goes up. Level P4 is therefore a narrower strip cut than level P3.
Among paper shredders for sale, the cross-cut shredder is generally used when information to be destroyed is less sensitive and less likely to be sought after.
P-security level factors were standardized in Germany by the official DIN 63399 standard set by the German Institute for Standards. This means that P-security levels related to shredding practices are internationally standardised.
The P3 and P4 levels associated with cross-cut shredders give the following number of shred-strips per page: the P3 cross-cut gives 200 shreds per page (6mm x 50mm), and the P4 gives 400 shreds per page (4mm x 40mm).
As with its counterpart, the cross-cut shredder also cuts papers diagonally from both corners, the only difference is that the micro-cut shredder shreds far more thinly.
In addition to the security factors related to your specific paper-shredding tasks, the cross-cut shredder may be used to dispose of more effectively documents which are no longer in use, as well as to shred paper strips for packaging purposes.
Cross-cut shredders are generally used for shredding personal, relatively low confidentiality documents such as bank statements, personal correspondence, or general business documents and memoranda.
2.  Micro-Cut
Micro-cut shredders are used for higher security documents, and these shredders cut at security levels P5, P6, and P7. The first two of these factors are still in the micro-cut category, but security level P7 is known as a nano-cut.
The security level P5 shred (2mm x 15mm) yields 2000 shred pieces per page, with levels P6 and P7 growing progressively finer. Among the two kinds of paper shredders for sale, the micro-cut option therefore shreds the page into fragments more than 10 times smaller than the cross-cut type.
Micro-cut shredders, also known as security-cut shredders, clearly offer a much higher level of data protection, and are more suitable for use in environments where highly confidential documents are produced.
The types of documents for which these levels of shredding are required are confidential contracts, medical and related information, and government or NGO documents of a very sensitive kind.
Whereas cross-cut particles (also known as confetti-cut or diamond-cut) can conceivably be reconstructed by experts, micro-cut particles are hardly readable and create almost impossible challenges for document reconstruction.
The choice of shredder is therefore strongly relevant to the level of security that is necessitated by the degree of confidentiality or security in the documentation environment.
