We've had a few questions on what the plot types mean, so this is here to clean that up!
To set a plot to a type, you can do /plot set <type name>. The <type name>'s are listed below.
It costs $500 from the town bank to set a plot type.
Arena - PVP is on all the time in arena plots as well as friendly-fire damage. Town health regen is also disabled in arena plots.
Bank - A plot designed for /t deposit & /t withdraw commands. Not required on CYT as we don't force the use of these for these commands.
Embassy - Allows outsiders from other towns to claim a plot in your town.
Farm - Allows players to kill animals, break and place crops, leaves and bee hives.
Inn - An Inn plot allows anyone to use a bed to set their /res spawn and spawn on death. The Inn plot will still deny a player who is in a nation declared as an enemy by your nation.
Jail - Mayors and police can jail and unjail residents by typing /town toggle jail <player>. Jailed residents will be sent to a jail plot if one exists.
Outpost - A town claim away from your main town area.
Shop - Allows the use of Chest Shops to be built on these.
Wilds - Designates a semi-protected wilderness plot, where trees, flowers, mushrooms etc can be broken but all other blocks cannot.
Identifying a Plot
To find out what type a plot is, you first need to know what a plot is. 1 plot = 1 chunk.
You can enable viewing chunk borders by pressing F3+G on Windows, and CMD+F3+G on Mac. Then you'll need to do /towny map big and that'll pop up with a list of plots (chunks) nearby and a key to identifying them.
For example, a green $ would indicate a plot for sale in your town that you can buy, whilst a white $ would indicate a plot that's for sale in a different town.
To purchase a plot, simply stand on a plot that is for sale and type /plot claim.