Float

A value with decimal places is interpreted as double by default. Use f to specify as float literal, e,g,

MyVariable = 1.2f;
MyVariable = -1.2f;
MyVariable = -1.f;    //Note the decimal point is required otherwise values is seen as an integer and a compiler error generated

Unsigned

‘u’ or ‘U’ to indicate an unsigned constant, like 33u
‘ul’ or ‘UL’ to indicate an unsigned long constant, like 32767ul