This is mainly a EPiServer 6 / Webforms approach.
If no pagebase object is readable:
<%= EPiServer.Core.LanguageManager.Instance.Translate("/mygadget/index/hello") %>
EPiServer.PageBase method xml/xslt path to value:
<p><%= Translate("/productlist/links/viewallcleaningpkgandacc")%></p>
Through asp.net get resource $ dot notated path to xml value
<%$ Resources: EPiServer, productlist.buttons.buyonline %>
Only valid inside server tags e.g:
<asp:Label runat="server" Text="<%$ Resources: EPiServer, productlist.buttons.buyonline %>" />
Web control episerver native (xml path to value):
<EPiServer:Translate runat="server" LocalizedText="/productlist/links/viewallcleaningpkgandacc" />