I need help identifying a screw

There are two screws that need to be removed to access the hard drive on the bottom of my Sony vaio vpcee41fx laptop. One

of them is easily removed with a Phillips screw driver but I'm having trouble finding a screw driver to remove the other

one. The other screw has what appears to be a circular indentation on the top of it. What type of screw driver do I need

to remove this screw? Thanks in advance for any help.

Here are a couple of images of the screw I am talking about. I know they're low quality and blurry but it's the best I

could do with what I had. All replies are appreciated.

[url=http://postimg.org/image/emc4488o5/][img]http://s18.postimg.org/emc4488o5/image.jpg[/img][/url]
http://postimg.org/image/emc4488o5/

[url=http://postimg.org/image/wof0743bf/][img]http://s17.postimg.org/wof0743bf/image.jpg[/img][/url]
http://postimg.org/image/wof0743bf/

[url=http://postimg.org/image/npdbey5e7/][img]http://s11.postimg.org/npdbey5e7/image.jpg[/img][/url]
http://postimg.org/image/npdbey5e7/

[url=http://postimg.org/image/vzrvc29l3/][img]http://s15.postimg.org/vzrvc29l3/image.jpg[/img][/url]
http://postimg.org/image/vzrvc29l3/