Permissions... Done right.
Permissions allows plugin-authors to utilize a permission system that handles 
group inheritance, globalized permission settings, and more. All the features 
of a fine-grained permission system in one plugin.

This is a continuation of the work that was originally done by Nijikokun.  All
original credit goes to them as without their work this plugin would not have
been possible.

Features:
Groups
Group Inheritance, Allows for groups to gain permissions from other groups.
User Permission System
Fine Grained Permission system.
Allowing for Globalized permissions
Easy to use, setup, and implement.
Two cache layers, first from file to memory, then from memory to cache.
Plugins can control cache since version 2.1

And much more.
AntiBuild functionality.
build: actually does something now within the config files. If you don't want a group to be able to build set it to build: false.
If a person is a member of multiple groups (inheritance) they will still be able to build unless all groups that they are inheriting 
and part of are set to build: false

For the admins
First thing that you will need to do is download the plugin. Place it in your plugins/ folder and unzip it. This should create the 
folder Permissions and a Permissions.jar file in your plugins folder. Next, go into Permissions/ and rename the config file that 
is in there to the name of your world. So if your world name from server.properties is Foo you will need to rename the config file 
to Foo.yml. You MUST rename it to whatever your worlds name is or it will not work and you must keep the .yml extension.

Next, you will need to go in and add yourself to the users, just replace the user that is in there with your name. Make any other
modifications that you need to. While making modifications make sure that you do NOT use tabs. These will break the YAML format
and cause issues. Instead, each indent should be four spaces. If you want people who aren't in the Admin group to be able to reload the 
permissions plugin you need to give them 'permissions.reload' permissions within the config file.

Also, make sure that whichever group has the '*' permissions, does not inherit from any other group. It's not needed and could 
potentially break things.

Permissions gives server admins great control, mostly in-game reloading. Simply use /permissions -reload all and the file will be 
re-cached and never touched again until you need to reload it. This allows you to quickly give your users the commands that they 
need without having to restart the server.

FAQ
[Q] I am getting an error that it can't pass BLOCK_PLACED or BLOCK _BREAK events to Permissions. Fix it!
[A] That's not a question. The reason why it can't place these is probably because the syntax of your Permissions file is all 
whacked out, or it is a different world and you don't have a config file 
for that world.

[Q] What am I suppose to name the config file?
[A] You need to name it the same as your world. So if you look in server.properties at "level-name" you will see a world name 
there. Rename your config file to the same thing as that. Make sure you 
keep the .yml extension at the end.

[Q] What does copies: do in the config file?
[A] That is only used if you have multiple worlds and should only be used on the extra worlds. If you fill that in with the 
name of another world (Such as the default one) then it will copy all the 
permissions from that world to this one.

[Q] Permissions are broken. Why can no one use commands? Why am I not an admin?
[A] First off, make sure that your formatting is correct. Look at the format that the default config file uses. Yours should 
look like that. Do NOT use tabs. Use 4 spaces (IE. " " <-- Four of those 
things.). Also, whichever group you give the permission '*' to, do not have that group inherit permissions from anyone else. 
That is called overloading and it will break things.

[Q] Which one am I suppose to download and unzip to install this?
[A] Download the main package, not the JAR only. Unzip the ZIP file. The JAR only downloads are simply there for people who are 
UPGRADING and do not need the default config file.

[Q] I have done all of this and this doesn't work! I'm going back to GroupManager!
[A] Well, there is probably the problem. Make sure that you delete EssentialsGroupManager.jar and EssentialsGroupBridge.jar as 
these don't play well with Permissions and will cause headache.

[Q] When are you going to add <blah> <feature/command> into this already? You suck! Do what I want NAU PL0X!
[A] Well, that's not really a plan. There is Yeditor that will work, and I am working on my own external plugin to allow you to 
modify commands, groups, users, and nodes. I also go to school full time, work two jobs, am starting my own business, have my own 
minecraft server, and several other plugins that I maintain and/or created. So I do tend to get busy at times. I do make this 
plugin the priority over all the others, but I still have to make time for everything else. (I already failed Sociology once 
because of to many demands on time and am close to failing it again because of taking over this plugin and it eating my life)