As per the Wikipedia, Deforestation, clearance or clearing is the removal of a forest or stand of trees where the land is thereafter converted to a non-forest use. Examples of deforestation include conversion of forestland to farms, ranches, or urban use.
It has been stipulated that almost more than half of the global plants and animals live in the tropic. Human are continually looting the tropical evergreen rainforests without thinking deeply on where is going to be the next habitat for the plants and animals.
Generally, people take it for granted taking the meaning of deforestation as only cutting down of trees in the tropics. We must also put in mind that there another term called regeneration whereby trees are being cut down in the tropics just to restructure their settlements to a much more sustainable realm
Deforestation happens in many ways such cutting down of trees without planting them and using them for furniture, timber logs meant for exports, to be used as fuels, sometimes they are even burned to form charcoal especially common in Africa. Sometimes also used as pasture to feed cattle, flocks etc.
In the cause of doing all this, we tend to forget that we are endangering the lives of plants and animals therefore destroying their habitat.
Oil palm plantations are a prevalent feature of the Malaysian landscape, as this industry has become a major contributor to the country?s export earnings.
The increase in palm oil production has been driven by strong global demand for oils and fats, notably from Europe and China. 
However, due to the massive expansion of the oil palm plantation, ?the fate of a magic floodplain in Sabah is in jeopardy?? This includes the lower Kinabatangan floodplains in Sabah, stretching along the northeastern coast of borneo, forests have been reduced to scattered pieces, while endangered animals such as elephants have lost their natural homes, thereby intensifying Flood.
Because the remaining forest is fragmented, elephants are forced to move through plantations and smallholdings to get from one patch to another. 
They prefer to use forest on dry ground, so during floods they are also forced into agricultural land, sometimes causing considerable damage.
Habitat fragmentation has also affected the orangutan populations and other species of high conservation priority (rhinoceros, monkeys, storm storks, oriental darters and others).
In a way to help check this, numerous international organizations as well as the United Nations and the World Bank, have begun to put in place some measures aimed at curbing deforestation. The blanket term Reducing Emissions from Deforestation and Forest Degradation (REDD) describes these sorts of programs, which use direct monetary or other incentives to encourage developing countries to limit and/or roll back deforestation. Some of the measures are as follows farming, monitoring deforestation, forest management, Sustainable practices, , forest plantations and last but not least, reforestation and in view of this that we took the league embark massive on tree planting exercises as our own way of bringing to mother earth what has being depleted away from it.