Simplenote
Simplenote is a note-taking program that supports Markdown. Cross-platform programs are available for Android, Linux, Windows, iOS, and macOS in addition to most web browsers. Simplenote provides an externally available API, which allows additional clients to be built, such as the macOS Dashboard widget DashNote and nvPY, a cross-platform Simplenote client. Furthermore, the macOS application Notational Velocity and the Windows software ResophNotes can sync with Simplenote.
Simplenote, a free and open-source note-taking tool, was developed by the Automattic (creators of WordPress) team to address your note-taking concerns. Syncing Simplenote across all of your devices–whether Windows, Mac, or mobile–is a useful function.
You also get markdown, which is quite useful for sharing code or emphasizing a point. On the other hand, there isn't a rich text editor. A drag-and-drop interface for revisions and note history is one feature that Simplenote has that others do not. To travel back in time, simply drag the toolbar.
Detailed information:
Cost: Free
Platforms: Android, iOS, Windows
Download: https://simplenote.com
