Disney Dollars have changed quite a bit since 1987, But they have also kept some key features too. Key features starting with the 1987 Disney Dollar that still continue through today:
Tinkerbell has always graced the Disney Dollar being a key element since 1987.
On every bill Scrooge McDuck is the signing treasurer. Scrooge is considered to be the business administrator, bank manager type, money saving, along with being cheap.
Disney Dollars just like other currency is not printed in unlimited quantities. Each bill has a specific serial number series year. These numbers/letters are specific and individual to each bill in order of when they are printed from 00000001 to 99999999. However, each set of bills has a limited quantity some have small production run such as for the limited edition $50 or large quantities for the $1.
On each side is a statement of denomination in the image below is the One Dollar on the reverse of the bill the the we can see the printer words, on the Obverse, or front, is the Numeral form
Since 1987 we have always seen an "important" character on each bill. These are Disney Characters of which primarily have been Mickey Mouse on the $1, Goofy on the $5 and Minnie Mouse on the $10. However In 2007, 2011, and 2014, a non character portrait has been used.
On each bill is and insignia to the left of the Main Character on the observe of the bill. This is typically the head of Mickey Mouse with an offset printing of the letter "D" inset. This image has changed seven times since 1987.