The Tigrinya Fidel is an Abugida or Alphasyllabary, in which each character represents a syllable rather than a single sound.
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Each consonant base can be modified to represent one of 7 vowels.
The apostrophe in the transliteration (') can represent a glottal stop on its own, or when combined with other sounds like (k') or (t') represent "ejective consonants."
The syllable bases are split into two lists to make quizzing yourself on them a little more manageable. There is also a word scramble game and a typing game to help you learn to read common words and put them together.
Tigrinya also has its own way of writing numbers. The Fidel originally comes from how the Ge'ez language was written and is mostly the same as the Amharic Fidel.