History
Up to the early 1990s, many programs and data transmission channels assumed that all characters would be represented as numbers between 0 and 127 (7 bits). On computers and data links using 8-bit bytes this left the top bit of each Byte free for use as a parity, flag bit, or meta data control bit. 7-bit systems and data links are unable to handle more complex character codes which are commonplace in non-English-speaking countries with larger alphabets.
Binary files cannot be transmitted through 7-bit data channels directly. To work around this, binary-to-text encodings have been devised which use only 7-bit ASCII characters. Some of these encodings are uuencoding, Ascii85, SREC, BinHex, kermit and MIME's Base64. EBCDIC-based systems cannot handle all characters used in UUencoded data. However, the base64 encoding does not have this problem.
Perhaps the final 7-bit restriction, primarily imposed due to the pervasive use of RS-232 protocol for serial ports between devices, notably computers and modems, was lifted in the mid-1990s when RS-232 was largely replaced with Ethernet and with USB.
Read more about this topic: 8-bit Clean
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“The history of men’s opposition to women’s emancipation is more interesting perhaps than the story of that emancipation itself.”
—Virginia Woolf (1882–1941)
“I am ashamed to see what a shallow village tale our so-called History is. How many times must we say Rome, and Paris, and Constantinople! What does Rome know of rat and lizard? What are Olympiads and Consulates to these neighboring systems of being? Nay, what food or experience or succor have they for the Esquimaux seal-hunter, or the Kanaka in his canoe, for the fisherman, the stevedore, the porter?”
—Ralph Waldo Emerson (1803–1882)
“Both place and time were changed, and I dwelt nearer to those parts of the universe and to those eras in history which had most attracted me.”
—Henry David Thoreau (1817–1862)