Inkscape is an open-source vector graphics editor similar to Adobe Illustrator, Corel Draw, Freehand, or Xara X. What sets Inkscape apart is its use of Scalable Vector Graphics (SVG), an open XML-based W3C standard, as the native format.
In contrast to raster (bitmap) graphics editors such as Photoshop or Gimp, Inkscape stores its graphics in a vector format. Vector graphics is a resolution-independent description of the actual shapes and objects that you see in the image. A rasterization engine uses this information to determine how to plot each line and curve at any resolution or zoom level.
Contrast that to bitmap (raster) graphics which is always bound to a specific resolution and stores an image as a grid of pixels.
Inkscape can import and display bitmap images, too. An imported bitmap becomes yet another object in your vector graphics, and you can do with it everything you can do to other kinds of objects (move, transform, clip, etc.)
While Inkscape does not have all the features of the leading vector editors, the latest versions provide for a large portion of basic vector graphics editing capabilities. People report successfully using Inkscape in a lot of very different projects (web graphics, technical diagrams, icons, creative art, logos, maps).
Inkscape 1.0 notable improvements:
- Theming support and more new customization options
- Better HiDPI (high resolution) screen support
- Native support for macOS with a signed and notarized .dmg file
- Coordinate origin in top left corner by default
- Canvas rotation and mirroring
- On-Canvas alignment of objects
- Split view and X-Ray modes
- PowerPencil for drawing editable, variable width strokes with a pressure sensitive graphics tablet
- New PNG export options
- Integrated centerline tracing for vectorization of line drawings
- Searchable Symbols dialog
- New Live Path Effect (LPE) selection dialog
- New Corners (Fillet/chamfer) LPE, (lossless) Boolean Operation LPE (experimental), Offset LPE and Measure Segments LPE (and more!)
- Path operations, deselection of a large number of paths as well as grouping/ungrouping are much faster now
- Much improved text line-height settings
- Variable fonts support (only if compiled with pango library version >= 1.41.1)
- Browser-compatible flowed text
- Extensions programming interface updated, with many new options
- Python 3 support for extensions [full release notes]