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The table below mostly uses Devanagari but it also includes letters from Bengali (purple) and Tamil (green) to illustrate the transliteration of non-Devanagari characters.
Many systems provide a way to select Unicode characters visually. ISO/IEC 14755 refers to this as a screen-selection entry method.
Microsoft Windows has provided a Unicode version of the Character Map program (find it by hitting ⊞ Win+R then type charmap then hit ↵ Enter) since version NT 4.0 – appearing in the consumer edition since XP. This is limited to characters in the Basic Multilingual Plane (BMP). Characters are searchable by Unicode character name, and the table can be limited to a particular code block. More advanced third-party tools of the same type are also available (a notable freeware example is BabelMap).
macOS provides a "character palette" with much the same functionality, along with searching by related characters, glyph tables in a font, etc. It can be enabled in the input menu in the menu bar under System Preferences → International → Input Menu (or System Preferences → Language and Text → Input Sources) or can be viewed under Edit → Emoji & Symbols in many programs.
This section needs expansion. You can help by adding to it. (September 2016)
Only certain fonts support all Latin Unicode characters for the transliteration of Indic scripts according to the ISO 15919 standard. For example, Tahoma supports almost all the characters needed. Arial and Times New Roman font packages that come with Microsoft Office 2007 and later also support most Latin Extended Additional characters like ḍ, ḥ, ḷ, ḻ, ṁ, ṅ, ṇ, ṛ, ṣ and ṭ. The open-source fonts Libertinus Serif and Libertinus Sans (forked from the Linux Libertine project) also have full support.
Literature
Aggarwal, Narindar K. 1985 (1978). A Bibliography of Studies on Hindi Language and Linguistics. 2nd edition. Indian Documentation Service / Academic Press: Gurgaon, Haryana.
See p 24-26 for table comparing Indic languages,
and p 33-34 for Devanagari alphabet listing. "Annex-F: Roman Script Transliteration" (PDF). Indian Standard: Indian Script Code for Information Interchange — ISCII. Bureau of Indian Standards. 1 April 1999. p. 32. Retrieved 20 November 2006.
External links
Typing a macron – page from Penn State University about typing with accents