Learning
<p><b>Learning</b> is the act of acquiring new, or modifying and reinforcing, existing <a href="http://en.wikipedia.org/wiki/Knowledge" title="Knowledge">knowledge</a>, <a href="http://en.wikipedia.org/wiki/Behavior" title="Behavior">behaviors</a>, <a href="http://en.wikipedia.org/wiki/Skill" title="Skill">skills</a>, <a href="http://en.wikipedia.org/wiki/Value_%28personal_and_cultural%29" title="Value (personal and cultural)">values</a>, or <a href="http://en.wikipedia.org/wiki/Preference" title="Preference">preferences</a> and may involve synthesizing different types of <a href="http://en.wikipedia.org/wiki/Information" title="Information">information</a>. </p>
<p>
The ability to learn is possessed by humans, animals and some <a href="http://en.wikipedia.org/wiki/Machine_learning" title="Machine learning">machines</a>. Progress over time tends to follow <a href="http://en.wikipedia.org/wiki/Learning_curve" title="Learning curve">learning curves</a>. Learning is not compulsory; it is contextual. It does not happen all at once, but builds upon and is shaped by what we already know. To that end, learning may be viewed as a process, rather than a collection of factual and procedural knowledge. Learning produces changes in the organism and the changes produced are relatively permanent.<sup id="cite_ref-Schacter_1-0" class="reference"><a href="http://en.wikipedia.org/wiki/Learning#cite_note-Schacter-1"><span>[</span>1<span>]</span></a></sup></p>
<p>
Human learning may occur as part of <a href="http://en.wikipedia.org/wiki/Education" title="Education">education</a>, <a href="http://en.wikipedia.org/wiki/Personal_development" title="Personal development">personal development</a>, schooling, or <a href="http://en.wikipedia.org/wiki/Training" title="Training">training</a>. It may be <a href="http://en.wikipedia.org/wiki/Goal-oriented" title="Goal-oriented" class="mw-redirect">goal-oriented</a> and may be aided by <a href="http://en.wikipedia.org/wiki/Motivation" title="Motivation">motivation</a>. </p>
<p>
The study of how learning occurs is part of <a href="http://en.wikipedia.org/wiki/Educational_psychology" title="Educational psychology">educational psychology</a>, <a href="http://en.wikipedia.org/wiki/Neuropsychology" title="Neuropsychology">neuropsychology</a>, <a href="http://en.wikipedia.org/wiki/Learning_theory_%28education%29" title="Learning theory (education)">learning theory</a>, and <a href="http://en.wikipedia.org/wiki/Pedagogy" title="Pedagogy">pedagogy</a>. </p>
<p>
Learning may occur as a result of <a href="http://en.wikipedia.org/wiki/Habituation" title="Habituation">habituation</a> or <a href="http://en.wikipedia.org/wiki/Classical_conditioning" title="Classical conditioning">classical conditioning</a>, seen in many animal species, or as a result of more complex activities such as <a href="http://en.wikipedia.org/wiki/Play_%28activity%29" title="Play (activity)">play</a>, seen only in relatively intelligent animals.<sup id="cite_ref-2" class="reference"><a href="http://en.wikipedia.org/wiki/Learning#cite_note-2"><span>[</span>2<span>]</span></a></sup><sup id="cite_ref-3" class="reference"><a href="http://en.wikipedia.org/wiki/Learning#cite_note-3"><span>[</span>3<span>]</span></a></sup> </p>
<p>
Learning may occur <a href="http://en.wikipedia.org/wiki/Conscious" title="Conscious" class="mw-redirect">consciously</a> or without conscious awareness. Learning that an aversive event can't be avoided nor escaped is called learned helplessness.<sup id="cite_ref-4" class="reference"><a href="http://en.wikipedia.org/wiki/Learning#cite_note-4"><span>[</span>4<span>]</span></a><span></span></sup>
<sup id="cite_ref-4" class="reference"><span> </span></sup>
There is evidence for human behavioral learning <a href="http://en.wikipedia.org/wiki/Prenatal" title="Prenatal" class="mw-redirect">prenatally</a>, in which <a href="http://en.wikipedia.org/wiki/Habituation" title="Habituation">habituation</a> has been observed as early as 32 weeks into <a href="http://en.wikipedia.org/wiki/Gestation" title="Gestation">gestation</a>, indicating that the <a href="http://en.wikipedia.org/wiki/Central_nervous_system" title="Central nervous system">central nervous system</a> is sufficiently developed and primed for learning and memory to occur very early on in <a href="http://en.wikipedia.org/wiki/Developmental_psychology" title="Developmental psychology">development</a>.<sup id="cite_ref-5" class="reference"><a href="http://en.wikipedia.org/wiki/Learning#cite_note-5"><span>[</span>5<span>]</span></a></sup>
Play has been approached by several theorists as the first form of learning. Children experiment with the world, learn the rules, and learn to interact through play. <a href="http://en.wikipedia.org/wiki/Lev_Vygotsky" title="Lev Vygotsky">Lev Vygotsky</a> agrees that play is pivotal for children's development, since they make meaning of their environment through play. 85 percent of brain development occurs during the first five years of a child's life.<sup id="cite_ref-His_Highness_The_Aga_Khan_IV_6-0" class="reference"><a href="http://en.wikipedia.org/wiki/Learning#cite_note-His_Highness_The_Aga_Khan_IV-6"><span>[</span>6<span>]</span></a></sup></p>