Some of the key features of the Symbol MT font include:
If you use specific symbols rarely (like "ℵ" - Alef or "℘" - Weierstrass p), you don't want to scroll through the character map. Symbol Mt Font
If you receive a technical manual, engineering document, or scientific paper from the 1990s or early 2000s, it almost certainly uses the Symbol Mt font (or its predecessor). To view these documents correctly today, you must have Symbol Mt installed. Without it, Greek letters will appear as gibberish Latin characters (e.g., "a" instead of "α"). Some of the key features of the Symbol
You cannot use Symbol Mt inside an Excel formula's syntax (Excel reads raw text). However, you can use it as a Chart Title or Axis Label. Without it, Greek letters will appear as gibberish
The Mac equivalent is usually called "Symbol" (not Symbol Mt). However, Mac users can install the Windows TrueType version.
The "Mt" in the name likely refers to Monotype, the foundry behind its design.