Types of noticing
Noticing aspects of the language to which you are attending – noticing the automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy.
Noticing the difference between what you hear or read and what you produce – noticing the automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy.
Types of knowledge
automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy knowledge is shown when learners can apply the rule and can also state the rule they are applying.
automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy knowledge is knowledge of the correct form without the ability (without conscious effort) to state what the rule is.
One purpose of raising learners' ability to notice language is to make the implicit explicit and the explicit automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy.
Learning vs. Acquisition
A central tenet of Krashen's view is that there is a distinction between learning (a automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy process of rule gathering) and acquisition (an automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy, natural process of learning which comes almost without effort).
Input vs. Intake
There is a distinction between automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy (the information the learner is exposed to) and automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy (the information the learner actually assimilates).
There is some evidence that if learners have to focus on automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy and meaning simultaneously, then intake may be reduced rather than enhanced.
Once is never enough in terms of noticing. If you really want input to result in intake, learners have to be automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy with noticing opportunities.
For input to become intake, and for an item to become embedded in automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy memory, data have to be automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy in some way, by, for example, saying aloud what we have heard or writing what we have read.
Learners need not only to employ a skill, they need also to be able to say automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy skill they are using and automaticconsciousExplicitfloodedformgapImplicitinputintakelanguagelong-termprocessedunconsciouswhatwhy.