Released yesterday, the latest developer preview build for Microsoft's Windows 10 brings a large number of changes to the operating system. New features include a more easily resizeable user interface for the Start menu and Action Center, the ability to pin favorite Web sites and other improvements to the Edge Web browser, Cortana intelligent digital assistant, and a pen-based handwriting experience.

The Windows Insiders preview build is available for both PC and Windows 10 Mobile developers. Other improvements arriving with this preview are a new panel for quicker and easier selection of emojis, new phone keyboard-like experiences for PCs, and a one-touch microphone button for desktop dictation in English or Chinese.

New 'Fluid Design' Elements

The Build 16215 for PC and Build 15222 for Mobile improvements feature new elements from Microsoft's Fluid Design System, Windows and Devices Group software engineer Dona Sarkar wrote yesterday on the Windows 10 blog. Unveiled at last month's Build developer conference, Fluid Design is designed to "deliver intuitive, harmonious, responsive and inclusive cross-device experiences and interactions," according to Microsoft.

The improved user interface allows users to more easily and smoothly resize the Start menu and Action Center frame vertically and horizontally, as well as diagonally, Sarkar said. The UI also enables a smoother transition from PC to tablet mode.

With this latest build, Microsoft is also rolling out a number of improvements to its Edge Web browser. One brings back a feature requested by users: pinned sites.

"We heard your feedback, and . . . in this build you can now pin a Web site to the taskbar from Microsoft Edge," Sarkar said. By choosing the "pin this page to the taskbar" option in the settings menu, users can add the icons of their favorite sites to the desktop taskbar for quick, one-click access.

Other Edge improvements include a new full-screen viewing option, the ability to annotate ePub books, new highlighting colors for PDFs viewed in the browser, and the ability to ask questions of Cortana while viewing PDFs in Edge.

Camera Roll-Based Cortana Reminders

The new Windows 10 build also introduces several improvements to Cortana. One update lets users request reminders from Cortana about events and activities based on images in their camera rolls. For example, a photo of a concert poster can prompt a message from Cortana that says, "I can help you keep track of this," with a one-tap "remind me" option.

Users with the pen accessory, supported by such devices as the Surface Pro 4 and Surface Studio, can also choose a new "Cortana Lasso" option from settings to circle time information for events on their screens. Doing so opens up similar reminder prompts from Cortana.

Several new handwriting-related capabilities are also arriving with this latest Windows 10 build. For example, users writing notes in the handwriting panel can now lift their pens off their screens for a moment to open up additional writing space with an overflow feature. They can also ink over errors in handwritten text to correct incorrect letters or misspelled words.

Another new handwriting feature lets users edit notes with four new gestures: strikethrough, scratch, join, and split. The split feature, for example, allows someone to break one word into two with a simple vertical stroke between the appropriate letters.

English-speaking users will also see improvements to the handwriting recognition engine designed to improve accuracy, Sarkar said. And those writing in both Chinese and English at once can switch to a new English mode for improved handwriting recognition in that language.

Users who have misplaced their digital pens can also get new help locating them by clicking "find my device." While digital pens aren't equipped with GPS, the new tool provides possible locations based on where they were last used.

Other updates will bring enhanced text prediction for desktop keyboards, a new desktop option for a one-handed touch keyboard, and improvements to My People, the night light, video playback settings, and the Game bar.