Here are the classes, structs, unions and interfaces with brief descriptions:

Qore::Thread::AbstractSmartLock	The abstract base class for locks that support the internal API for use with the Condition class
Qore::Thread::AutoGate	A helper class for the Gate class for exception-safe Gate handling
Qore::Thread::AutoLock	A helper class for the Mutex class for exception-safe Mutex handling
Qore::Thread::AutoReadLock	A helper class for the RWLock class for exception-safe read lock handling
Qore::Thread::AutoWriteLock	A helper class for the RWLock class for exception-safe write lock handling
Qore::Thread::Condition	Can be used For blocking a thread until a condition becomes True
Qore::Thread::Counter	Implements a class that can be used for blocking a thread until a counter reaches zero
Qore::SQL::Datasource	This class provides the Qore interface to databases
Qore::SQL::DatasourcePool	Provides transparent per-thread, per-transaction datasource connection pooling
Qore::Dir	This class implements directory handling, file listing, creating/removing subdirectories, etc
Qore::File	The File class allows Qore programs to read, write, and create files
Qore::FtpClient	Allows Qore code to communicate with FTP servers with the FTP and FTPS protocols
Qore::Thread::Gate	Implements a reentrant thread lock
Qore::GetOpt	The GetOpt class provides an easy way to process POSIX-style command-line options in Qore scripts/programs
Qore::HTTPClient	Can be used to communicate with HTTP servers with and without TLS/SSL encryption
Qore::Thread::Mutex	A class providing an implementation for a simple thread lock
Qore::Program	Program objects allow Qore programs to support subprograms with the option to restrict capabilities, for example, to support user-defined logic for application actions
Qore::Thread::Queue	Queue objects provide a blocking, thread-safe message-passing object to Qore programs
Qore::Thread::RWLock	Implements a read-write thread lock
Qore::Thread::Sequence	Implements a thread-safe increment-only object
Qore::Socket	Allows Qore programs safe access to network sockets
Qore::SQL::SQLStatement	Most flexibilty for executing SQL on a database server
Qore::SSLCertificate	SSLCertificate objects allow Qore code to work with X.509 certificate data
Qore::SSLPrivateKey	This class implements a container for private key data
Qore::TermIOS	This class allows Qore scripts to get or set terminal settings on UNIX platforms
Qore::TimeZone	Access to time zone functionality
<binary>	Methods in this pseudo-class can be executed on binary values
<bool>	Methods in this pseudo-class can be executed on booling-point values
<callref>	Methods in this pseudo-class can be executed on call references
<closure>	Methods in this pseudo-class can be executed on closures
<date>	Methods in this pseudo-class can be executed on date/time value types
<float>	Methods in this pseudo-class can be executed on floating-point values
<hash>	Methods in this pseudo-class can be executed on hash values
<int>	Methods in this pseudo-class can be executed on integer values
<list>	Methods in this pseudo-class can be executed on lists
<object>	Methods in this pseudo-class can be executed on objects
<string>	Methods in this pseudo-class can be executed on strings
<value>	Methods in this pseudo-class are available to be executed on any value type (even NOTHING); this is the root class for all pseudo-classes