Paste a text face and see every character in it. Try it with ( ͡° ͜ʖ ͡°) or ヽ༼ຈل͜ຈ༽ノ.
Is ツ a smiley?
No, it is a letter. ツ is "tsu" in katakana, one of the Japanese writing systems. Its two short strokes and long curve just happen to look like a smiling face. That is why it became the face in the shrug ¯\_(ツ)_/¯. シ, the letter "shi", looks almost the same. The difference is the angle of the strokes.
The small ッ is used in Japanese to double the next sound. ㋡ is ツ inside a circle.
The old smileys ☺ and ☻
☺ and ☻ were smileys long before emoji. They were in the character set of the first IBM PC in 1981, and Unicode later gave them the codes U+263A and U+263B. Some phones now draw ☺ as a color emoji, so it may not look the same on every screen.
Which scripts do text faces borrow from?
The faces on this site use 737 different characters from 79 parts of Unicode. These are the parts they use most:
Unicode block
Characters used
Basic Latin
67
Combining Diacritical Marks
46
Box Drawing
39
Halfwidth and Fullwidth Forms
38
Mathematical Operators
37
Geometric Shapes
35
Miscellaneous Symbols
29
Unified Canadian Aboriginal Syllabics
26
Latin-1 Supplement
25
General Punctuation
25
Faces mix letters from many languages. ಠ is a Kannada letter from India, ຈ is from Lao, ༼ ༽ are Tibetan marks and ل is the Arabic letter lam. Combining marks like ͡ have no width of their own. They sit on top of the letter before them, which is how the lenny face gets its eyebrows.
Why do some parts show as boxes?
A box or a question mark means your device has no font with that character. The face is not broken. It will show up fine on a device that has the font.