draw.io is a free online diagramming application that allows you to create and share diagrams. The application is available for Windows, Mac, and Linux. draw.io is a web-based application that uses standard web technologies such as HTML, CSS, and JavaScript. The application is built on top of the Google App Engine. draw.io is a collaborative application that allows you to create and share diagrams with others.

Inkscape

Inkscape is an open-source vector graphics editor with capabilities similar to Illustrator, CorelDRAW, or Xara X. What sets Inkscape apart is its use of Scalable Vector Graphics (SVG), an open W3C standard, as the native format.

Vectr

Vectr is a free graphics editor used to create vector illustrations. It's available for both desktop and web (with a Chrome app). Vectr's interface is clean and intuitive, making it a great choice for anyone who's just getting started with vector graphics.

Adobe Illustrator

Adobe Illustrator is the industry-standard vector graphics editor, used by professionals around the world. It's packed with powerful features, but its interface can be daunting for beginners.

Sketch

Sketch is a vector graphics editor for MacOS with a focus on user experience and ease of use. It's become a popular choice for designing user interfaces and icons.

GIMP

GIMP is a free and open-source raster graphics editor, similar to Adobe Photoshop. It has a wide range of features and can be used for everything from simple photo editing to complex image manipulation.