Typesetting Malayalam on computers became an issue with their spread in the late 20th century. The lack of diacritics on keyboards led to the adoption of ASCII only romanisation schemes. ASCII only schemes remain popular in email correspondence and input methods because of their ease of entry. These schemes are also called Manglish. The disadvantage of ASCII schemes is that letter case is meaningful, so that transliterated names may not be capitalised.
Mozhi
The Mozhi system of transliteration[1] is an unofficial system used to transliterate Malayalam, it can also be used for Tamil. This system does not need the use of diacritics.
Even though it has more elaborate scheme, Mozhi[2] is as follows:
aa i ii u uu R RR
e E ai o O au Ll Lll am aH
k kh g gh ng
ch chh j jh nj
T Th D Dh N
th thh d dh n
p ph b bh m
y r l v
S sh s h
L zh rr t
ITRANS
ITRANS is an ASCII scheme which does not use diacritics for transliteration to Latin script.