What is the difference (if any) between Html.Partial(view, model) and Html.RenderPartial(view,model) in MVC2?

Other than the type it returns and the fact that you call it differently of course

<% Html.RenderPartial(...); %>
<%= Html.Partial(...) %>  

If they are different, why would you call one rather than the other one?
The definitions:

// Type: System.Web.Mvc.Html.RenderPartialExtensions
// Assembly: System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
// Assembly location: C:\Program Files (x86)\Microsoft ASP.NET\ASP.NET MVC 2\Assemblies\System.Web.Mvc.dll

using System.Web.Mvc;

namespace System.Web.Mvc.Html
{
    public static class RenderPartialExtensions
    {
        public static void RenderPartial(this HtmlHelper htmlHelper, string partialViewName);
        public static void RenderPartial(this HtmlHelper htmlHelper, string partialViewName, ViewDataDictionary viewData);
        public static void RenderPartial(this HtmlHelper htmlHelper, string partialViewName, object model);

        public static void RenderPartial(this HtmlHelper htmlHelper, string partialViewName, object model,
                                     ViewDataDictionary viewData);
    }
}

// Type: System.Web.Mvc.Html.PartialExtensions
// Assembly: System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
// Assembly location: C:\Program Files (x86)\Microsoft ASP.NET\ASP.NET MVC 2\Assemblies\System.Web.Mvc.dll

using System.Web.Mvc;

namespace System.Web.Mvc.Html
{
    public static class PartialExtensions
    {
        public static MvcHtmlString Partial(this HtmlHelper htmlHelper, string partialViewName);

        public static MvcHtmlString Partial(this HtmlHelper htmlHelper, string partialViewName,
                                        ViewDataDictionary viewData);

        public static MvcHtmlString Partial(this HtmlHelper htmlHelper, string partialViewName, object model);

        public static MvcHtmlString Partial(this HtmlHelper htmlHelper, string partialViewName, object model,
                                        ViewDataDictionary viewData);
    }
}

The only difference is that Partial returns an MvcHtmlString, and must be called inside <%= %>, whereas RenderPartial returns void and renders directly to the view.

If you look at the source code, you'll see that they both call the same internal method, passing a StringWriter for it to render to.

You would call Partial if you want to view, save, or manipulate the generated HTML instead of writing it to the page.

[This is a great explanation by Dino Esposito:][1]

> The difference between the two methods may look small and harmless, > but it may bite at you if you don’t know how to handle it. The key > difference between the two methods is: > > - Partial returns a HTML-encoded string > - RenderPartial is a void method that writes directly to the response output stream. > > The usage of the two methods is slightly different: > > @Html.Partial("_yourPartialView") > @{ Html.RenderPartial("_yourPartialView "); } > > The choice of which to use depends on your requirements. If you need > to further manipulate the string being injected in the response > stream, you should use Partial; otherwise go with RenderPartial > which is-just because it goes straight to the stream-a little faster > than Partial. > > In the end, the use-cases for partial views fall in either of two > camps. The first is when you create a view by composing together > various independent pieces of markup, as below. > > > @{ Html.RenderPartial("_Header"); } > @Html.Partial("_Sidebar") >

> @{ Html.RenderPartial("_Footer"); } > > > In this case, your decision in choosing between RenderPartial or > Partial doesn’t change the final effect. However, because > RenderPartial is slightly faster, you may prefer using it. > > >
[1]:https://www.red-gate.com/simple-talk/dotnet/asp-net/tips-and-tricks-about-razor-partial-views/

The Html.Partial and Html.RenderPartial are extension method is a reusable portion of a web page. The return type of RenderPartial is void, where as Partial returns MvcHtmlString. Html.RenderAction will render the result directly to the Response Stream (More efficient & fast) whereas Html.Action returns a string (which can be manipulated) with the result.