Succession is the process by which a habitat changes over time as different plants get established.
Primary Succession
Series of community changes which occur on an entirely new habitat which has never been colonised by plants before.
Secondary Succession
The colonisation of plants within an environment which has been colonised previously but damaged or disturbed e.g. fire, flood, deforestation.
At each stage of succession (sere) species are adapted to thrive and will compete against other species under a specific set of environmental conditions.
Primary colonisers form a pioneer community.
Secondary succession occurs much faster than primary succession because there is already existing soils which retain nutrients and seeds.