Originally Posted by webconfigure
There are number of plugins provided by the WordPress for free or for the paid service. You can check the plugins on the WordPress's own site. Many times paid plugins are preferred as there are multiple functionality and modification can be easily done.
While paid does tend to be of a degree better. Personally I try to only pay for software that are open source and includes software level support. In order to limit "vendor lock ins" and other problems with proprietary coded software.