Special characters that are actually two letters combined into one. In cases where two adjacent characters would normally bump into each other, a ligature allows the letters to flow together more gracefully. This usually makes word shapes more aesthetically pleasing. Some common ligatures are “fi", “fl”, “ff”, “ffl”, etc.

connecting of certain characters and printing them as one. Examples are 'ff', 'fl' and 'fi'.

A thread used to tie a blood vessel during an operation

To be tied or to tie someone up causes compression which produces physical and psychological pleasure to the subservient partner. The ligatures are part of bondage techniques.