Micromanagement

Micromanagement, frequently shorterned to Micro, refers to player actions of actively aiming a tower, activating an ability, or some other gameplay task which is not automated by the game. Examples include aiming Dartling Gunners, Collecting Bananas, or rapidly switching target priorities and flight paths.

Targeting Micro
The easiest micro to execute, this is a simple yet efficient way to make sure your towers deal as much damage as possible, or to avoid targeting specific bloon(s), or vice versa. For example, if you leave a sniper on first, especially 3-x-x snipers and above, they might hit low tier bloons, resulting in a high damage loss. However, setting them on strong makes sure they maximize their damage output. Sometimes this kind of micro needs to be constantly done, for example switching a tower on strong to whittle down large bloons, then setting it on first to catch leaks.

Selling and Rebuying Micro
Usually, this kind of micro is done with towers that have an ability. (as well as not having an initial cooldown.) This kind of micro allows player to shorten the cooldown between abilities, even reducing it to mere seconds with abilities that do not have an initial cooldown, such as the MOAB Eliminator and BTD6 Absolute Zero. However, be aware that it comes with a hefty price of losing quite some cash with each sell and rebuy. Sometimes, in Bloons TD Battles and Bloons TD Battles 2 a player may perform this kind of micro on a non-ability tower, with the tower sold usually being a money-making tower. For example, if the player is sent a large rush, they might quickly sell a Banana Farm to buy more defense, then sell the defense for another Banana Farm once the rush is defeated.

Heli Micro
Basically, it's done by moving the Heli Pilot to a specific location to make sure you get the best out of it, however with every path of the heli the micro is different. For the top path, it might be better to let the heli hit strong bloons, then move it to another location to clean up leaking bloons. For the middle path, you'll want to make sure that the maximum amount of bloons are blown away, or maybe even a specific group of bloons. For the bottom path, since its use is to stall MOABs, it is recommended to leave the heli nearby the blimps, buying time for your other towers to attack.

Mortar Micro
Mortar Micro is done by aiming at a spot that either gets as much bloons as possible, or to try and aim ahead of leaking bloons to catch them. Mortars such as The Big One and above, Artillery Battery and above are easier to micro, as they either have a big blast radius or shoot really fast. It is recommended to get the hang of the mortar you are trying to micro's attack speed and/or blast radius to get the most out of your mortar.

Dartling Micro
Dartling Micro is done by continually moving the Dartling Gunner to and from the needed locations. This can be done by the mouse/pointer (like Helis on Follow Mouse/Touch), or by lock-and-relocate (like Mortars). Doing so will change its angle accordingly. It may have some delay in moving to and from different angles, at least in BTD6 for sure, but it works effectively.

Ace Micro
The hardest of micro, Ace Micro is done by switching your ace's flight pattern to make sure that a lot of darts hit their target. This is usually done with top path and middle path aces, with the middle path micro called Bomber Ace micro. The patterns are made to keep the ace to the top, right, bottom, left etc. to the landing pad. The patterns are too complicated to explain here, but once you've got the hang of it, it only relies on muscle memory.

Another form of ace micro was introduced in 27.0, due to Centered Path gaining the newfangled ability to change the location of the path's centre like how a Mortar Monkey can change targets.