Language Translation in VisualForce Page

SK_LocalizationDemo.vf

<apex:page standardcontroller="Account" extensions="SK_LocalizationDemoController" language="{!selectedLang}" sidebar="false">
<apex:form >
    <div >
        <div style="float:right">
            <apex:selectList value="{!selectedLang}" size="1">
                <apex:selectoptions value="{!AvailableLanguages}"/>
                <apex:actionsupport event="onchange"/>
            </apex:selectlist>
        </div>
    </div>
    
    <div id="maincontainer">
        
        <apex:pageblock >
            <apex:pageblocksection >
                <apex:inputfield value="{!Account.Name}"/>
                <apex:inputfield value="{!Account.Type}"/>
                <apex:inputfield value="{!Account.Industry}"/>
                <apex:inputfield value="{!Account.BillingState}"/>
                <apex:inputfield value="{!Account.BillingCountry}"/>
                
                
            </apex:pageblocksection>
        </apex:pageblock>
        
    </div>
    
</apex:form>
</apex:page>

SK_LocalizationDemoController.cls

public class SK_LocalizationDemoController {
	public string selectedLang{get;set;}
    public SK_LocalizationDemoController(ApexPages.StandardController controller) {
		selectedLang='en';
    }

    
    public List<selectoption> getAvailableLanguages(){
    
        List<selectOption> options = new List<selectOption>();
        options.add(new selectOption('en','English'));
        options.add(new selectOption('de','German'));
        options.add(new selectOption('es','Spanish'));
        options.add(new selectOption('fr','French'));
        options.add(new selectOption('it','Italian'));
        
        options.add(new selectOption('ja','Japanese'));
        options.add(new selectOption('sv','Swedish'));
        options.add(new selectOption('ko','Korean'));
        options.add(new selectOption('zh_TW','Chinese (Traditional)'));
        options.add(new selectOption('zh_CN','Chinese (Simplified)'));
        options.add(new selectOption('pt_BR','Portuguese (Brazil)'));
        
        options.add(new selectOption('nl_NL','Dutch'));
        options.add(new selectOption('da','Danish'));
        options.add(new selectOption('th','Thai'));
        options.add(new selectOption('fi','Finnish'));
        options.add(new selectOption('fr','French'));
        options.add(new selectOption('ru','Russian'));
        
        options.add(new selectOption('es_MX','Spanish (Mexico) '));
        options.add(new selectOption('no','Norwegian'));
        options.add(new selectOption('pl','Polish'));
        options.add(new selectOption('cs','Czech'));
        options.add(new selectOption('tr','Turkish'));
        options.add(new selectOption('in','Indonesian'));
        
        options.add(new selectOption('uk','Ukrainian'));
        options.add(new selectOption('iw','Hebrew'));
        options.add(new selectOption('el','Greek'));
        options.add(new selectOption('en_GB','English (UK): '));
        options.add(new selectOption('ar','Arabic'));
        options.add(new selectOption('in','Indonesian'));
        
        return options;
    }
    
}