Keeping it simple, let's say I hold 100 shares of Catepillar in my IRA account. In 10 years (way before my retirement date), it goes up to $200/share, can I sell and have it sit in my "cash reserve" or whatever it's called? Do I have to tie my money to a fund or funds in order for it to not get hit by a penalty? My understanding is that if i withdraw, I will have to pay a penalty if I pull it out before my retirement age.