if i will start my own this type of site http://www.bigadda.com indiafm.com josh18.com/ What Type of hosting needed... what type of technology needed... any other from your side?
The questions are unanswerable as you could write a social network site in ASP, .Net, PHP, JSP, CFM, CGI, NSF, Ruby etc and depending on which of those you go for dictates what hosting you require in terms of linux/ windows/ unix etc and servers (IIS/ Apache/ Tomcat/ Domino etc) Hosting space is neither here nor there these days what will be the concerns are bandwidth and processor power. Ultimately if a site is successful it will not only require a dedicated server but a farm of them (from memory myspace uses more than 200 servers) but it is up to you if you want to start off on a dedicated machine or have the pain of switching over to one if the site starts getting big. These are really the questions your developer should be answering for you... remember to tell them who scalable you want the site - the capability to run well off multiple servers is going to cost a fair chunk of money so it is up to you to decide if you pay that now and save in the long term or have it built only suitable for single server and rebuilt later down the line