Time travel

Time travel, sometimes called TT'ing or time travelling, is the act of the player manually changing the time of their game to advance to a future event or go back to a past event without having to wait in real time.

Changing the time of date does not affect villagers, weeds, flowers, hair, trees, dump/recycling, mail, bell bank, turnips, police station/lost and found, or construction. It will, however, affect sun/moonlight season, weather, and the time until a holiday or event.

How to Time Travel
There are different ways to change the clock time in each console the games were released on. Below addresses how to change the clocks:

In Animal Crossing
To change the time in there are two options - the Nintendo GameCube clock or the in-game clock access through the in-game options. The ideal option is to change the GameCube's internal clock, because the in-game clock affects the growth of trees, the way letters are sent, and how the Police Station and Dump restock with items. However, the highest the game clock can go is December 31st, 2030.

To access the GameCube menu, players can hold 'A' while the GameCube is starting. Then, they should follow the on-screen options.

In Animal Crossing: Wild World
To change the time in-game, when players are at the character select, they can click the phone and follow the option that goes to the Date and Time settings.

To change the DS time, players can turn on the DS and then press the DS icon at the bottom of the touch screen (as long as the main DS menu appears). Then, they should choose the second, blue menu, which manipulates the time. The top button changes the date, the right button changes the time, and the middle one changes the alarm. The player should press "B" until it asks if the system should shut down. The player can press "A" and load the game as usual.

To change the DSi time, players can choose settings and the time and then press B and start the game as normal.

In Animal Crossing: City Folk
As in the original Animal Crossing, there are two options to change the date and time settings for. The easier option is to change the Wii date and time instead of the in-game date and time settings. This is again due to the in-game settings' affecting the bank interest, plants and trees.

To change the Wii time settings, players can enter the Wii Menu and select the 'Wii' button at the bottom left of the screen. Once there, players can go to 'Setup' and find the menu which opens the Date and Time settings.

The second way is to change the date and time of the game itself. When starting the game, select “other things” and there will be an option to change the date and time.

In Animal Crossing: New Leaf
To change the time, players must start the game talking to Isabelle. Instead of saying "yes, let's", they must say " I need help first...". Now, the player should press 'set date/time' and set the date/time they would like to travel to.

In Animal Crossing: New Horizons
New Horizons is the first game in the series that does not have an in-game option to change the time. To change the Switch system time, go to System Settings → System → Date and Time. Then turn off "Synchronize Clock via Internet" and set the time. The effects of time travel are lessened in this game, possibly due to content and events being rolled out in updated over time, which is a first in the series.

The effects of time travelling
There are advantages and disadvantages to time travelling. Below are the positive and negative effects on the game:

Positive

 * Allows the player to attend out-of-season events.
 * Allows the player to receive mail sooner.
 * Allows the player to receive bank interest.
 * New villagers move in sooner.
 * Fruit grow on trees sooner.
 * Different items available at all stores.
 * Ability to catch out-of-season fish and bugs.
 * Ability to gain facilities sooner (e.g., sewing machine, Shampoodle)

Negative

 * Villagers move away (unless done properly).
 * There are more weeds (using Wisp by finding his lamp can solve this).
 * Flowers are shrivelled or missing.
 * The player misses sales in GracieGrace, Able Sisters, Tom Nook's Store and Re-Tail.
 * The player's mailbox may fill, which disallows incoming mail until it is emptied.
 * The player gets bed head.
 * Turnips rot.
 * Phineas is gone for a while.

Other Effects

 * Villagers start referring to the player as a 'time traveler'