Infringement
Infringement occurs when one does something that only the copyright owner has the exclusive rights to do or when one engages in an unauthorised use. For example, if one were to reproduce any copyright materials without the prior permission of the copyright owner.

It is important to note that it is not necessary to have reproduced the entire copyright work before it is considered infringing. It is infringing as long as a substantial amount has been copied.

In a dispute, a substantial amount is not measured merely in terms of the quantity that has been copied. The Court also takes into account the nature of the portion that has been copied or reproduced. If the portion copied constitutes the primary part or essence of the copyright material, the Court may construe that a substantial amount has been copied.

It is also an infringement to:
a) import infringing copies for sale or distribution;
b) distribute infringing copies for trade;
c) distribute infringing copies to an extent that will prejudicially affect the owner of copyright; or
d) falsely attributes the authorship of a work.

source: http://www.newiplaws.org.sg/index.htm