Shadowed boxes and empty boxes
The box ❒ is officially the upper right shadowed white square (U+2752). It belongs to a set of four from the Dingbats block: ❏ and ❐ have a drop shadow, ❑ and ❒ a flat shadow. They give lists and headings a slightly 3D look and make good bullets in bios. ⧉ (two joined squares) looks like the "copy" or "new window" icon in many apps.
For a plain empty box, use ☐ (ballot box), ▢ (rounded corners) or □ (white square). ⬚ has a dotted outline, ▣ has a smaller square inside, and ⌧ shows an X in a box. For solid and colored squares, see the square symbols page.
Checkbox symbols for lists and forms
For to-do lists and printable forms, the trio ☐ ☑︎ ☒ is all you need: empty, ticked and crossed out. 🗹 has a bolder tick and 🗷 a bold X. In plain text without symbols, people write [ ] and [x], and in Markdown on GitHub, - [ ] and - [x] at the start of a line become a real task list.
In Microsoft Word, type 2610 and press Alt + X for ☐, 2611 for ☑︎ or 2612 for ☒. More ticks and X marks are on the check mark symbol page.
Draw a box around text
Box-drawing characters let you frame text line by line: ┌──┐ on top, │ on each side and └──┘ at the bottom. On Windows, the Alt codes are Alt + 218 ┌, Alt + 191 ┐, Alt + 192 └, Alt + 217 ┘, Alt + 196 ─ and Alt + 179 │. The lines only join up neatly in a monospace font, such as a code block in Discord.
For ready-made frames and fancier corners like ╔ ╗ ╭ ╮, see the border symbols page. Brackets like 【 】 are an easy way to box a single word, and the bracket symbols page has many more.