A. Initial (starting) Controls

Your starting controls..are..

Arrow keys - Move
ALT - Jump
CTRL - Attack
1 - Chat to All (talk to the public)
2 - Chat to Party (talk to your party/group)
3 - Chat to Buddy (talk to your friends)
Z - Pick up (Items, mesos (gMS currency), etc.)
x - Sit down (on bench or chair, if available)
M - Minimap (your current map)
W - World Map (of Victoria Island only)
E - Equipment (what you’re wearing)
I - Inventory (what you have in your inventory)
S - Ability (your stats - STR, INT, DEX, and LUK)
H - Whisper (directly and privately to ONE player) (copies the
player’s name to clipboard)
K - Skill (your skills - unique to your job class)
R - Buddy/Party member list
F1-7: Facial Expressions

Those are all the ones I can memorize, and the mandatory ones for
a good experience in MapleStory (MS for short).

B. About Customizing your Controls

You can also customize your controls for a comfortable playing
experience. You can customize your controls through KEY SETTINGS
(on the toolbar at the bottom of the screen, the keyboard keys).

My controls:

ALT - Drain (skill)
Shift - Lucky Seven (skill)
CTRL - Claw Booster (skill)
Delete - Dark Sight (skill)
1 - Chat to All
2 - Party Chat
3 - Buddy Chat
4 - Guild Chat (appears in Key Settings after you’ve joined a guild)
R - Buddy/party member list
T - Guild member list
B - Ability
N - Pick up

And everything else is the starting controls.

As you can see above, you can assign your skills to specific
keys on your keyboard.

You can also assign POTIONS (recover your health, mana points, and
can increase your stats for a temporary period of time) and return
scrolls (bring you back to a certain town),for quick access to them.