Use telnet to test HTTP server

A few year ago, I managed a few hundred of servers, they provide HTTP service using Apache.
I often need to test the HTTP service on these servers.

I used telnet for my testing

C:\>telnet www.redhat.com 80
GET /robots.txt HTTP/1.1
host: www.redhat.com

HTTP/1.1 200 OK
Server: Apache
X-Powered-By: Servlet 2.5; JBoss-5.0/JBossWeb-2.1
Last-Modified: Fri, 27 Jan 2012 23:35:31 GMT
Accept-Ranges: bytes
Content-Length: 484
Content-Type: text/plain; charset=UTF-8
Cache-Control: no-cache
Date: Tue, 08 May 2012 12:20:11 GMT
Connection: keep-alive

User-agent: *

Disallow: /apps/download/results.html
Disallow: /apps/search/results.html
Disallow: /apps/user/
Disallow: /apps/user/*
Disallow: /WebX/*
Disallow: /webx/*
Disallow: /WebX/*
Disallow: /test_community/
Disallow: /test_community/*
Disallow: /network
Disallow: /archives/redhat-install-list/2000-September/msg00588.html
Disallow: /search
Disallow: /search*
Disallow: /mailman/listinfo/ceylon-core
Disallow: /mailman/private/ceylon-core/
Disallow: /mailman/admin/ceylon-core