There are several standard methods to encode Japanese characters for use on a computer, including JIS, Shift-JIS, EUC, and Unicode. While mapping the set of kana is a simple matter, kanji has proven more difficult. Despite efforts, none of the encoding schemes have become the de facto standard, and multiple encoding standards were used by 2000s. As of 2017, the usage share of UTF-8 on the Internet has expanded to over 90 % worldwide, and rest of 1.2% used Shift-JIS and EUC. Yet, a few popular websites including 2channel and kakaku.com are still using Shift-JIS.