One of my friend who goes to the business school is doing some research on finding which is the most popular webserver on which commercial websites are deployed.
The key parameters to study are scalability,security ,cost and ease of maintenance . He will be doing his research but he needs some pointers to get started. Please tell what you think about this. If you could point to some technical papers then this will also be appreciated.
Finally I am sorry in advance if you think that this is a homework question( but he just needs to get started in the right direction). In that case I will request the community support to delete this question immediately.