Tactical Aide Memoire.
Generally useful for remembering your Orders headings, using the framework of Mission Command, especially when your 1/3-2/3 rule tells you that there is only three minutes for you to write them and you can see the OC, CSM, CSgt or anyone else who may realise you haven't a scooby what's going on and were thinking about your Girlfriend's assets when the OC was telling you about the Enemy's and yours (See Officer Cadet or Young Officers).
Usually contains a mysterious Arm supplement on the right hand binder which is horribly confusing and should be covered by your blank TAMs paper, to avoid mental overload, at all costs. Even the Infantry one, whilst using easy to follow words, is mysterious and dangerous.
Some chaps like to put fancy little binder inserts in so they know where important bits of their TAMs are. Pink is to be avoided as, at some point, an NCO will ask to see them and you will suffer for it- if an Ocdt it will be the last straw to making the spring in the DS mind pop. If a young officer, you may be transferred to a joint services post with the RN and RAF, as they like that type of thing. However if you are Cavalry it is expected, it shows panache.
Finally, it is useful for padding out your 'platoon commander breasts' and helps you look the part, even when you don't have a scooby it may well buy you a few precious minutes to decide how far you could get before the WO2, RMP or CSgt can catch you.