Chris Winters in his 'Paper on mod_perl' notes that 'Apache uses a pre-forking model
to handle many web requests at once. What this means is that on startup, the httpd
program (known as the parent) will spawn a number of children, each of which is a
fully functioning web server.'
The number of httpd processes you see may be normal your installation. I see 8 when
I look at the active process with 'ps -ef|grep htttpd'.
to find his paper.