Older "legacy" fonts often show up as question marks or weird symbols if the other person doesn't have the exact same font installed. Using an ensures your text is readable by everyone, everywhere—whether in an email, on Facebook, or in a Word document.
Before the IME Kit, popular tools like (for Sinhala) and Kural or Murasu Anjal (for Tamil) dominated the market. How does the native IME Kit compare? sinhala tamil ime kit for windows 10
For users who prefer "transliteration" (typing in English sounds to get local script), these tools are highly rated: Older "legacy" fonts often show up as question
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