有关问题很低级，就想搞明白

问题很低级，就想搞明白，请指教
为什么php 的mail就能自动发邮件呢，发邮件不是都要STMP服务器的帐号和密码吗
mail(to,subject,message,headers,parameters)，为什么这样就可以发了，是不是每台电脑都装了stmp服务啊，有点迷糊

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谁说不要配置呢？

[mail function]
; For Win32 only.
; http://php.net/smtp
SMTP = localhost
; http://php.net/smtp-port
smtp_port = 25

; For Win32 only.
; http://php.net/sendmail-from
;sendmail_from = me@example.com

; For Unix only. You may supply arguments as well (default: "sendmail -t -i").
; http://php.net/sendmail-path
;sendmail_path =

; Force the addition of the specified parameters to be passed as extra parameters
; to the sendmail binary. These parameters will always replace the value of
; the 5th parameter to mail(), even in safe mode.
;mail.force_extra_parameters =

; Add X-PHP-Originating-Script: that will include uid of the script followed by the filename
mail.add_x_header = On

; The path to a log file that will log all mail() calls. Log entries include
; the full path of the script, line number, To address and headers.
;mail.log =
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你可以看下php。ini中相关配置
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说明apecha里已经配置哦了
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是有个！
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