The focus in this article is on changes in ownership and use of personal computer（ PC） and in these of the Internet. In 1999 and 2009, authors carried out questionnaire surveys including questions about PC/Internet ownership in Kure City, Hiroshima Prefecture. The findings of this article based on these surveys are follows.
　1. Popularization of PC: In 2009, 84 percent of respondent had PC, up from 40 percent in 1999.There were relationships between PC ownership and gender, age, educational attainment andfamily income in 1999. These relationships were weakened in 2009. In particular, the chi-square
test of significance for the relationship between PC ownership and gender of the respondent did not establish a statistically significant relationship between the two variables. From an age analysis it was found that the rate of PC ownership among the 20s do not rise so much as that among other ages from 1999 to 2009.
　2. Transition of PC from a computing machine to an Internet terminal: In 2009, 70 percent of respondent had Internet access at home, up from 19 percent in 1999. Many people in 20s and 30s use the Internet.
　3. Abating of posting to social network services（ SNS） via PC: In 2009, 31 percent of respondent having Internet access posted to SNS, down from 47 percent in 1999. The abating of posting may be caused not only by the spread of mobile phone but also by privatization of Japanese youth.