# Global objects The AxoSyslog application uses the following objects: * _Source driver_ : A communication method used to receive log messages. For example, AxoSyslog can receive messages from a remote host via TCP/IP, or read the messages of a local application from a file. For details on source drivers, see [source: Read, receive, and collect log messages](../../docs/axosyslog-core/chapter-sources/index.md). * _Source_ : A named collection of configured source drivers. * _Destination driver_ : A communication method used to send log messages. For example, AxoSyslog can send messages to a remote host via TCP/IP, or write the messages into a file or database. For details on destination drivers, see [destination: Forward, send, and store log messages](../../docs/axosyslog-core/chapter-destinations/index.md). * _Destination_ : A named collection of configured destination drivers. * _Filter_ : An expression to select messages. For example, a simple filter can select the messages received from a specific host. For details, see [Customize message format using macros and templates](../../docs/axosyslog-core/chapter-manipulating-messages/customizing-message-format/index.md). * _Macro_ : An identifier that refers to a part of the log message. For example, the `${HOST}` macro returns the name of the host that sent the message. Macros are often used in templates and filenames. For details, see [Customize message format using macros and templates](../../docs/axosyslog-core/chapter-manipulating-messages/customizing-message-format/index.md). * _Parser_ : Parsers are objects that parse the incoming messages, or parts of a message. For example, the `csv-parser()` can segment messages into separate columns at a predefined separator character (for example, a comma). Every column has a unique name that can be used as a macro. For details, see [parser: Parse and segment structured messages](../../docs/axosyslog-core/chapter-parsers/index.md) and [db-parser: Process message content with a pattern database (patterndb)](../../docs/axosyslog-core/chapter-parsers/chapter-patterndb/index.md). * _Rewrite rule_ : A rule modifies a part of the message, for example, replaces a string, or sets a field to a specified value. For details, see [Modify messages using rewrite rules](../../docs/axosyslog-core/chapter-manipulating-messages/modifying-messages/index.md). * _Log paths_ : A combination of sources, destinations, and other objects like filters, parsers, and rewrite rules. The AxoSyslog application sends messages arriving from the sources of the log paths to the defined destinations, and performs filtering, parsing, and rewriting of the messages. Log paths are also called log statements. Log statements can include other (embedded) log statements and junctions to create complex log paths. For details, see [log: Filter and route log messages using log paths, flags, and filters](../../docs/axosyslog-core/chapter-routing-filters/index.md). * _Template_ : A template is a set of macros that can be used to restructure log messages or automatically generate file names. For example, a template can add the hostname and the date to the beginning of every log message. For details, see [Customize message format using macros and templates](../../docs/axosyslog-core/chapter-manipulating-messages/customizing-message-format/index.md). * _Option_ : Options set global parameters of `syslog-ng`, like the parameters of name resolution and timezone handling. For details, see [Global options](../../docs/axosyslog-core/chapter-global-options/index.md). For details on the above objects, see [The configuration syntax in detail](../../docs/axosyslog-core/chapter-configuration-file/configuration-syntax/index.md). Last modified June 27, 2023: [Update paths to follow-up moving the files (6585a5b)]()