Windows-1254 is a code page used under Microsoft Windows to write Turkish. Characters with codepoints A0 through FF are compatible with ISO 8859-9, but the CR range, which is reserved for C1 control codes in ISO 8859, is instead used for additional characters (analogous to the relationship between ISO-8859-1 and Windows-1252). The WHATWG Encoding Standard, which specifies the character encodings which are permitted in HTML5 and which compliant browsers must support, includes Windows-1254, which is used for both the Windows-1254 and ISO-8859-9 labels. Unicode is preferred for modern applications; authors of new pages and the designers of new protocols are instructed to use UTF-8 instead. As of 2020, 0.1% of all web pages use Windows-1254, and 0.1% use ISO-8859-9, which the WHATWG requires the browser to handle as Windows-1254. However, 2.3% of all websites located in Turkey use Windows-1254, and 3.1% of them use ISO-8859-9. IBM uses code page 1254 (CCSID 1254 and euro sign extended CCSID 5350) for Windows-1254.