Lossy compressors don't have the same constraints as a lossless compressor. If you data your input, compress it, and then decompress it, the output is not identical to the input. This allows the compressor to potentially compress the data far more than even the ideal lossless compressor hypothesized above.
The question mark (?), also known as the interrogation point, query, and eroteme, is a punctuation mark that indicates an interrogative clause, or phrase in many languages. The question mark is not used for indirect questions.
As a verb, to tick (off) or to check (off) means to add such a mark. It is quite common, especially on printed forms, printed documents, and computers (see check box), for there to be squares in which to place ticks. Read Wikipedia article to find out more about its meaning and using.hat tick signs mean. A tick (also known as a check mark or check) is a mark used to indicate the concept yes, for example yes; this has been verified, yes; that is the correct answer, yes; this has been completed, or yes; this [item or option] applies to me.