Should you leave on a localhost?

I’ve been studying web development for almost a year and I recently switched from hosting my files on the local file system to using a localhost, WAMP. One thing I’m not sure about is whether or not it’s OK to leave WAMP on while I’m not using it. Is that OK? My concern is that it might interfere with the normal operation of the computer but I don’t know if that’s true. What do you guys do?

I haven’t used a WAMP package yet. I have installed Apache, MySQL and PHP individually myself and have had no problem with anything interfering with the normal operation of any programs. I go into the Services screen in the Control Panel and set the services’ startup type to manual from automatic so they don’t run when the computer is booted. I also put an line in an htaccess file in the document root to deny connections from all but localhost.

You should have no problems allowing these services to run when you are not using them. I haven’t and I’ve been using them for years.

When I used WAMP (I use a CentOS VM in VirtualBox now) I had it running all the time. Never had any a problem with it. No weird stuff going on, no slowing down, etc.
You may want to make sure the host isn’t accessible from the internet to avoid getting hacked/hacking attempts, but if you’re using a router that’s most likely no problem as most routers don’t have any port forwarding set up by default.