! # % & * + - / : < = > ? @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z [ ^ ` { |
            
- uc
    
- Character classes
    - uc
- ul
    
- Character classes
    - ul
- unattached
    
- global, local, constant, field
- Unicode
    
- Character set encoding
- union
    
- union
- Unix
    
- Platforms
- unless
    
- do when, do unless
    - when, unless
- unlock file
    
- vfs.unlock
- unprefixed
    
- import, supply, prefixed by, unprefixed, use
- updating records in a table
    
- db.update
- uppercase
    
- uc
    - ul
- upto
    
- Pattern matching
- up-translate
    
- Managing coroutines
- use
    
- import, supply, prefixed by, unprefixed, use
- usemap
    
- usemap
- user defined data type
    
- record, declare record
    - Records
    - Records, extended
- using
    
- using
    - using group
    - using input as
    - using nested-referents
    - using output as
- using group
    
- Groups
    - using group
- using input as
    
- Input
    - using input as
- using nested-referents
    
- Referents
    - using nested-referents
- using output as
    
- Output
    - output
    - using output as
- UTF 16 conversion filters
    
- UTF-16 (OMFFUTF16)
    - utf16.reader
    - utf16.writer
- UTF-8
    
- Character set encoding