Why not total it up? Take everything you have, find out how much space it will take, see whether or not it's more or less than 64GB.
Also, you're talking about storage not memory. Memory is RAM, short term. Storage is the HDD or SSD in this case, but long term regardless. You also need to remember to leave a couple GB for the OS and apps, so if your music and what not totals over I'd say 50GB, I'd start looking at the 128GB or even 256GB options.
And keep in mind that Apple does not consider the Air to be a user upgradeable system. In fact, they use these obnoxious 5-point torx screws which is rather difficult to find a screwdriver for. It can be done, but given that the SSD is a special form factor, and the RAM, CPU, and GPU are hard soldered to the logic board, there's really no point for the average person to ever remove the bottom case from the thing. There's nothing for you to do but look at what's in there unless you work at an AASP. So, if you're going to buy an Air, more than any other laptop you may ever buy, you need to make sure that you get EVERYTHING you're going to want/need for the duration. On most other systems it's possible to skimp a little and make up for it later, but not the MacBook Air. Be sure to factor that into your plans.
I am interesting in buying the MacBook Air 11.6 model with 64GB of disk space, and am wondering if that space is enough for most?
If you have the 64GB model, does your memory eat up quickly? What is this type of disk space ideal for?
I have about 5GB of music, 15 movies, and 7 seasons of TV. I plan on buying an external hard drive anyways to back up my data, so I can have the movies on that.
Will 64GB suffice?
Thanks!

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