1. OpenStreetMap (OSM) A free, community-based mapping project with global coverage. OSM data can be freely used, modified, and integrated into custom projects — making it ideal for genealogical websites, as it often includes historical place names and small settlements.
➡Strengths: High level of detail, open license (ODbL), editable, versatile interfaces.

2. OpenTopoMap A topographic map service based on OSM data, with contour lines, terrain shading, and natural features. Especially useful for visualizing historical landscapes, such as old borders, rural areas, or natural terrain.
➡Strengths: Topographic style, excellent for geographic and terrain analysis.

3. Google Maps A commercial map service by Google, known for global coverage, high accuracy, and ease of use. Features like Street View, satellite images, and route planning are widely appreciated.
➡Strengths: User-friendly, high-resolution imagery, extensive APIs.
➡Limitations: License required for many types of integrations (e.g., on public websites).

4. Wikimedia Maps Based on OSM and primarily used in Wikipedia articles. The maps are usually simplified but stable, multilingual, and easy to reuse under the CC BY-SA license. A good fit for basic location displays in articles or documentation.
➡Strengths: Easy integration, consistent styling, Wikimedia-compatible.