Introducing VisualforceOver the past several years, Salesforce has created a comprehensive platform for building on-demand applications. Like other sophisticated application development platforms, the Force.com platform offers separate tools for defining:The structure of the data—that is, the data model
The rules that detail how that data can be manipulated—that is, the business logic
The layouts that specify how that data should be displayed—that is, the user interface

Please check below post. I hope that will help you
https://developer.salesforce.com/docs/atlas.en-us.pages.meta/pages/
http://amitsalesforce.blogspot.in/search/label/Visual%20Force%20Page
Vf page life cycle :-
http://amitsalesforce.blogspot.in/2015/04/visualforce-page-life-cycle-in.html
Some tag
http://amitsalesforce.blogspot.in/2015/02/defining-templates-with-apexcomposition.html
http://sfdcsrini.blogspot.com/2014/06/visualforce-form-tags-with-examples.html
<apex:page>
<apex:form> 
<apex:pageblock> 
<apex:pageBlockSection>
<apex:commandButton>
<apex:pageBlockButtons> 
<apex:commandLink> 
<apex:outputLink> 
<apex:inputField>
<apex:inputFile> 
<apex:inputHidden>
<apex:inputsecret> 
<apex:inputText> 
<apex:inputTextarea>
<apex:inputCheckbox> 
<apex:outputField> 
<apex:outputLabel>
<apex:outputText> 
<apex:pageBlockSectionItem> 
<apex:pageBlockTable> 
<apex:column> 
<apex:dataTable> 
<apex:tabPanel>
<apex:tab> 
<apex:toolbar> 
<apex:toolbarGroup> 
<apex:pageMessage> 
<apex:panelBar> 
<apex:panelBarItem>
<apex:panelGrid>
<apex:panelGroup> 
<apex:param>
<apex:repeat>
<apex:facet>
<apex:actionFunction>
<apex:detail> 
<apex:actionPoller> 
<apex:actionRegion> 
Message Class
<apex:variable>
<apex:stylesheet>
Referencing a Static Resource in Visualforce Pages
<apex:SectionHeader >
<apex:relatedList>
<apex:listViews>
<apex:enhancedList>
<apex:actionStatus> 
<apex:actionSupport>

Please let us know if this will help you