[root@blog ~]# vi /etc/nginx/conf.d/default.conf

server {
listen 80;
server_name localhost;

#charset koi8-r;
#access_log  /var/log/nginx/host.access.log  main;

location / {
    root   /usr/share/nginx/html;
    index  index.php index.html index.htm;
}
    .........code
.........code
......code
    #自己加的 ;意思是当用户请求到gif|jpg|jpeg等等...的文件会自动缓存到用户的电脑上，
    下次就不用在给用户一份了，提升用户的体验
location ~ .*\.(gif|jpg|jpeg|png|bmp|swf)$
            {
                  expires 30d;
             }
}