Nowadays, geoprocessing has moved in large parts from isolated desktop usage into the Web. Thereby, the overall availability of geoprocessing functionality has theoretically improved. Nevertheless, web-based geoprocessing functionality is still not readily available and usable as means to find and subsequently compare functionality are yet missing. Discoverability and exchangeability of geoprocessing functionality are limited, and the fundamental benefits of online usage are not fully exploited. To close this gap, this thesis defines a conceptualization with geooperators representing well-defined geoprocessing functionality, and categories representing distinct geooperator attributes as a starting point. Geooperators and categories are connected by associative and hierarchical links forming an interlinked network. The conceptualization serves as basis for two purposes:\nOn the one hand, discovery of geooperators has to be improved. There is a multitude of different GIS users from varying backgrounds, all having a slightly different view on geoprocessing functionality. To embrace these varying views, several actually existing and established categorizations for geooperators are integrated into the conceptualization and structured hierarchically. Thus, multiple different perspectives on geooperators are enabled. The perspectives and the underlying categorizations are integrated into a geooperator browser serving as client that users can employ for discovery. The geooperator browser offers a faceted browsing interface based on the derived perspectives and categories. Several different search modes are offered and can be used simultaneously, thereby facilitating an improved discovery.\nOn the other hand, to establish comparability and subsequently semantically interoperable exchangeability of geooperators, respective geooperator attributes are defined. Thereby, backend and provider independence of geoprocessing services is achieved. The conceptualization is formalized to allow for machine readability and processing which is required for usage in Spatial Data Infrastructures and the Semantic Web. The formalized conceptualization is labeled geooperator thesaurus. It is encoded by Semantic Web standards and offered in a Semantic Web compliant manner. The integration into geoprocessing service metadata is enabled by injecting semantic annotations that link to the respective concepts in the geooperator thesaurus. The thesaurus serves as the underlying data model for the geooperator browser.\nThe thesis concludes with an outlook and discussions of future work. Foremost, the content of the geooperator thesaurus needs to be extended as it currently only comprises a representative subset of geooperators. An approach is suggested to involve the geoprocessing community as an important source of geoprocessing expertise in the maintenance and further development of the thesaurus. On a conceptual level, the thesaurus needs to be extended to a fully-fledged ontology including a formal geoprocessing algebra to support the creation of geooperator workflows. From a discovery point of view, the concept of geoprocessing patterns is outlined. Geoprocessing patterns list geooperators that are commonly used for certain geoprocessing tasks, and provide best practices about applying them in a meaningful manner and sequence.