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Further algorithms - Edexcel Variables and constants

It can contain letters and numbers but must start with a letter. It must contain at least one letter (at the start of the name). It must not contain special characters such as !@£$%&* or punctuation ...
BBC

Data types, structures and operators - Edexcel

It can contain letters and numbers but must start with a letter. It must contain at least one letter (at the start of the name). It must not contain special characters such as !@£$%&* or punctuation ...