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＞＞＞（1）如图1，在平行四边形ABCD中，点E，F分别在AB，CD上，AE=CF．求..
（1）如图1，在平行四边形ABCD中，点E，F分别在AB，CD上，AE=CF．求证：DE=BF．（2）如图2，在△ABC中，AB=AC，∠A=40°，BD是∠ABC的平分线，求∠BDC的度数．
题型：解答题难度：中档来源：山东省中考真题
（1）证明：∵四边形ABCD是平行四边形，∴AD=BC，∠A=∠C，在△ADE和△CBF中， AD=CB ，∠A=∠C ，AE=CF，∴△ADE≌△CBF（SAS)∴DE=BF；（2）解：∵AB=AC，∠A=40°∴∠ABC=∠C=（180°-40°）=70°，又∵BD是∠ABC的平分线，∴∠DBC=∠ABC=35°，∴∠BDC=180°-∠DBC-∠C=75°．
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据魔方格专家权威分析，试题“（1）如图1，在平行四边形ABCD中，点E，F分别在AB，CD上，AE=CF．求..”主要考查你对&&全等三角形的性质，三角形的中线，角平分线，高线，垂直平分线，平行四边形的性质&&等考点的理解。关于这些考点的“档案”如下：
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因为篇幅有限，只列出部分考点，详细请访问。
全等三角形的性质三角形的中线，角平分线，高线，垂直平分线平行四边形的性质
全等三角形：两个全等的三角形，而该两个三角形的三条边及三个角都对应地相等。全等三角形是几何中全等的一种。根据全等转换，两个全等三角形可以是平移、旋转、轴对称，或重叠等。当两个三角形的对应边及角都完全相对时，该两个三角形就是全等三角形。正常来说，验证两个全等三角形时都以三个相等部分来验证，最后便能得出结果。全等三角形的对应边相等，对应角相等。①全等三角形对应角所对的边是对应边，两个对应角所夹的边是对应边;②全等三角形对应边所对的角是对应角，两条对应边所夹的角是对应角;③有公共边的，公共边一定是对应边;④有公共角的，角一定是对应角;⑤有对顶角的，对顶角一定是对应角。全等三角形的性质：1.全等三角形的对应角相等。2.全等三角形的对应边相等。3.全等三角形的对应边上的高对应相等。4.全等三角形的对应角的角平分线相等。5.全等三角形的对应边上的中线相等。6.全等三角形面积相等。7.全等三角形周长相等。8.全等三角形的对应角的三角函数值相等。&三角形的中线：在三角形中，连接一个顶点和它对边的中点的线段叫做三角形的中线。由于三角形有三条边，所以一个三角形有三条中线。且三条中线交于一点。这点称为三角形的重心。每条三角形中线分得的两个三角形面积相等。角平分线：三角形的一个角的平分线与这个角的对边相交，这个角的顶点和交点间的线段叫做三角形的角平分线。 三角形的角平分线不是角的平分线，是线段。角的平分线是射线。高线：从三角形一个顶点向它的对边做垂线，顶点和垂足之间的线段叫做三角形的高线（简称三角形的高）。 线段的垂直平分线：经过某一条线段的中点，并且垂直于这条线段的直线，叫做这条线段的垂直平分线。
注意：要证明一条线为一个线段的垂直平分线，应证明两个点到这条线段的距离相等且这两个点都在要求证的直线上才可以证明巧计方法：点到线段两端距离相等。三角形中线性质定理：1、三角形的三条中线都在三角形内。
2、三角形的三条中线长：
ma=(1/2)√2b2+2c2 -a2 ；
mb=(1/2)√2c2 +2a2 -b2& ；
mc=(1/2)√2a2 +2b2 -c2& 。
(ma,mb,mc分别为角A,B,C所对的中线长）
3、三角形的三条中线交于一点，该点叫做三角形的重心。
4、直角三角形斜边上的中线等于斜边的一半。
5.三角形中线组成的三角形面积等于这个三角形面积的3/4.
定理内容：三角形一条中线两侧所对边平方和等于底边的一半平方与该边中线平方和的2倍。
角平分线线定理：定理1：在角平分线上的任意一点到这个角的两边距离相等。逆定理：在一个角的内部（包括顶点），且到这个角的两边距离相等的点在这个角的角平分线上。定理2：三角形一个角的平分线分对边所成的两条线段与这个角的两邻边对应成比例，如：在△ABC中，BD平分∠ABC，则AD：DC=AB：BC注：定理2的逆命题也成立。三角形的三条角平分线相交于一点，并且这一点到三条边的距离相等！(即内心)。
垂直平分线的性质：1.垂直平分线垂直且平分其所在线段。&& 2.垂直平分线上任意一点，到线段两端点的距离相等。&& 3.三角形三条边的垂直平分线相交于一点，该点叫外心，并且这一点到三个顶点的距离相等。&& 垂直平分线的逆定理：到一条线段两个端点距离相等的点，在这条线段的垂直平分线上。垂直平分线的尺规作法：方法一：1、取线段的中点。2、分别以线段的两个端点为圆心，以大于线段的二分之一长度为半径画弧线。得到一个交点。3、连接这两个交点。原理：等腰三角形的高垂直等分底边。方法二：1、分别以线段的两个端点为圆心，以大于线段的二分之一长度为半径画弧线，得到两个交点。原理：圆的半径处处相等。2、连接这两个交点。原理：两点成一线。 垂直平分线的概念：经过某一条线段的中点，并且垂直于这条线段的直线，叫做这条线段的垂直平分线（中垂线）平行四边形的概念：两组对边分别平行的四边形叫做平行四边形。平行四边形用符号“□ABCD，如平行四边形ABCD记作“□ABCD”，读作ABCD”。①平行四边形属于平面图形。②平行四边形属于四边形。③平行四边形中还包括特殊的平行四边形：矩形，正方形和菱形等。④平行四边形属于中心对称图形。平行四边形的性质：主要性质（矩形、菱形、正方形都是特殊的平行四边形。）（1）如果一个四边形是平行四边形，那么这个四边形的两组对边分别相等。（简述为“平行四边形的两组对边分别相等”）（2）如果一个四边形是平行四边形，那么这个四边形的两组对角分别相等。（简述为“平行四边形的两组对角分别相等”）（3）如果一个四边形是平行四边形，那么这个四边形的邻角互补（简述为“平行四边形的邻角互补”）（4）夹在两条平行线间的平行线段相等。（5）如果一个四边形是平行四边形，那么这个四边形的两条对角线互相平分。（简述为“平行四边形的对角线互相平分”）（6）连接任意四边形各边的中点所得图形是平行四边形。(推论）（7）平行四边形的面积等于底和高的积。（可视为矩形）（8）过平行四边形对角线交点的直线，将平行四边形分成全等的两部分图形。（9）平行四边形是中心对称图形，对称中心是两对角线的交点.（10）平行四边形不是轴对称图形，矩形和菱形是轴对称图形。注：正方形，矩形以及菱形也是一种特殊的平行四边形，三者具有平行四边形的性质。（11）平行四边形ABCD中（如图）E为AB的中点，则AC和DE互相三等分，一般地，若E为AB上靠近A的n等分点，则AC和DE互相(n+1)等分。（12）平行四边形ABCD中，AC、BD是平行四边形ABCD的对角线，则各四边的平方和等于对角线的平方和。（13）平行四边形对角线把平行四边形面积分成四等分。（14）平行四边形中，两条在不同对边上的高所组成的夹角，较小的角等于平行四边形中较小的角，较大的角等于平行四边形中较大的角。（15）平行四边形中,一个角的顶点向他对角的两边所做的高，与这个角的两边组成的夹角相等。
发现相似题
与“（1）如图1，在平行四边形ABCD中，点E，F分别在AB，CD上，AE=CF．求..”考查相似的试题有：
118043100836131972161719204241227371From Wikipedia, the free encyclopedia
This article's
does not adequately
key points of its contents. Please consider expanding the lead to
of all important aspects of the article. Please discuss this issue on the article's . (February 2013)
Base64 is a group of similar
schemes that represent
string format by translating it into a -64 representation. The term Base64 originates from a specific .
Each base64 digit represents exactly 6 bits of data. Three 8-bit bytes (i.e., a total of 24 bits) can therefore be represented by four 6-bit base64 digits.
The particular set of 64 characters chosen to represent the 64 place-values for the base varies between implementations. The general strategy is to choose 64 characters that are both members of a subset common to most encodings, and also . This combination leaves the data unlikely to be modified in transit through information systems, such as email, that were traditionally not . For example, MIME's Base64 implementation uses A–Z, a–z, and 0–9 for the first 62 values. Other variations share this property but differ in the symbols chosen for an example is .
The earliest instances of this type of encoding were created for dialup communication between systems running the same  — e.g.,
(later adapted for the ) — and could therefore make more assumptions about what characters were safe to use. For instance, uuencode uses uppercase letters, digits, and many punctuation characters, but no lowercase.
The Base64 index table:
The example below uses
text for simplicity, but this is not a typical use case, as it can already be safely transferred across all systems that can handle Base64. The more typical use is to encode
(such as an image); the resulting Base64 data will only contain 64 different ASCII characters, all of which can reliably be transferred across systems that may corrupt the raw source bytes.
A quote from ' :
Man is distinguished, not only by his reason, but by this singular passion from other animals, which is a lust of the mind, that by a perseverance of delight in the continued and indefatigable generation of knowledge, exceeds the short vehemence of any carnal pleasure.
is represented as a byte sequence of 8-bit-padded
characters encoded in 's Base64 scheme as follows:
TWFuIGlzIGRpc3Rpbmd1aXNoZWQsIG5vdCBvbmx5IGJ5IGhpcyByZWFzb24sIGJ1dCBieSB0aGlz
IHNpbmd1bGFyIHBhc3Npb24gZnJvbSBvdGhlciBhbmltYWxzLCB3aGljaCBpcyBhIGx1c3Qgb2Yg
dGhlIG1pbmQsIHRoYXQgYnkgYSBwZXJzZXZlcmFuY2Ugb2YgZGVsaWdodCBpbiB0aGUgY29udGlu
dWVkIGFuZCBpbmRlZmF0aWdhYmxlIGdlbmVyYXRpb24gb2Yga25vd2xlZGdlLCBleGNlZWRzIHRo
ZSBzaG9ydCB2ZWhlbWVuY2Ugb2YgYW55IGNhcm5hbCBwbGVhc3VyZS4=
In the above quote, the encoded value of Man is TWFu. Encoded in ASCII, the characters M, a, and n are stored as the bytes 77, 97, and 110, which are the 8-bit binary values , , and . These three values are joined together into a 24-bit string, producing . Groups of 6 bits (6 bits have a maximum of 26 = 64 different binary values) are
from left to right (in this case, there are four numbers in a 24-bit string), which are then converted into their corresponding Base64 character values.
As this example illustrates, Base64 encoding converts three
into four encoded characters.
source ASCII (if &128)
source octets
110 (0x6e)
Bit pattern
Base64-encoded
encoded octets
117 (0x75)
If there is only one significant input byte (e.g., 'M'), all 8 bits will be captured in the first two base64 digits (12 bits).
Text content
Bit pattern
Base64-encoded
If there are two significant input bytes (e.g., 'Ma'), all 16 bits will be captured in the first three base64 digits (18 bits). '=' characters might be added to make the last block contain four base64 characters.
Text content
Bit pattern
Base64-encoded
As illustrated in the first table above, when the last input group contains only one octet, the four
of the last content-bearing 6-bit block will turn out to be zero:
Bit pattern
Base64-encoded
And when the last input group contains two octets, the two least significant bits of the last content-bearing 6-bit block will turn out to be zero:
Bit pattern
Base64-encoded
The final '==' sequence indicates that the last group contained only one byte, and '=' indicates that it contained two bytes. The example below illustrates how truncating the input of the above quote changes the output padding:
any carnal pleasure.
YW55IGNhcm5hbCBwbGVhc3VyZS4=
any carnal pleasure
YW55IGNhcm5hbCBwbGVhc3VyZQ==
any carnal pleasur
YW55IGNhcm5hbCBwbGVhc3Vy
any carnal pleasu
YW55IGNhcm5hbCBwbGVhc3U=
any carnal pleas
YW55IGNhcm5hbCBwbGVhcw==
The same characters will be encoded differently depending on their position within the three-octet group which is encoded to produce the four characters. For example:
cGxlYXN1cmUu
bGVhc3VyZS4=
ZWFzdXJlLg==
The ratio of output bytes to input bytes is 4:3 (33% overhead). Specifically, given an input of n bytes, the output will be
{\displaystyle 4\lceil n/3\rceil }
bytes long, including padding characters.
In theory, the padding character is not needed for decoding, since the number of missing bytes can be calculated from the number of Base64 digits. In some implementations, the padding character is mandatory, while for others it is not used. One case in which padding characters are required is concatenating multiple Base64 encoded files.
Decoding Base64 with padding
When decoding Base64 text, four characters are typically converted back to three bytes. The only exceptions are when padding characters exist. A single '=' indicates that the four characters will decode to only two bytes, while '==' indicates that the four characters will decode to only a single byte. For example:
YW55IGNhcm5hbCBwbGVhcw==
any carnal pleas
YW55IGNhcm5hbCBwbGVhc3U=
any carnal pleasu
YW55IGNhcm5hbCBwbGVhc3Vy
any carnal pleasur
Decoding Base64 without padding
Without padding, after normal decoding of four characters to three bytes over and over again, fewer than four encoded characters may remain. In this situation only two or three characters shall remain. A single remaining encoded character is not possible (because a single base 64 character only contains 6 bits, and 8 bits are required to create a byte, so a minimum of 2 base 64 characters are required : the first character contributes 6 bits, and the second character contributes its first 2 bits) . For example:
YW55IGNhcm5hbCBwbGVhcw
any carnal pleas
YW55IGNhcm5hbCBwbGVhc3U
any carnal pleasu
YW55IGNhcm5hbCBwbGVhc3Vy
any carnal pleasur
Implementations may have some constraints on the alphabet used for representing some bit patterns. This notably concerns the last two characters used in the index table for index 62 and 63, and the character used for padding (which may be mandatory in some protocols, or removed in others). The table below summarizes these known variants, and link to the subsections below.
Char for index 62
Char for index 63
Fixed encoded line-length
Maximum encoded line length
Line separators
Characters outside alphabet
Line checksum
Original Base64 for
(RFC 1421, deprecated)
= (mandatory)
Yes (except last line)
Base64 transfer encoding for
(RFC 2045)
= (mandatory)
No (variable)
Accepted (discarded)
Standard 'base64' encoding for
= (mandatory unless specified by referencing document)
No (unless specified by referencing document)
none (unless specified by referencing document)
none (unless specified by referencing document)
Forbidden (unless specified by referencing document)
'Radix-64' encoding for
(RFC 4880)
= (mandatory)
No (variable)
(Radix-64-encoded, including one pad character)
Modified Base64 encoding for
(RFC 1642, obsoleted)
No (variable)
Modified Base64 encoding for
mailbox names ()
No (variable)
Standard 'base64url' with
Safe Alphabet ( §5 'Table 2: The "URL and Filename safe" Base 64 Alphabet')
= (optional if data length is known, otherwise must be percent-encoded in URL)
No (variable)
(application-dependent)
Unpadded 'base64url' (eg. )
No (variable)
(application-dependent)
(none, or separate
checksum in )
Non-standard -safe Modification of Base64 used in
No (variable)
(application-dependent)
Modified Base64 for
name tokens (Nmtoken)
No (variable)
(XML parser-dependent)
Modified Base64 for
identifiers (Name)
No (variable)
(XML parser-dependent)
Modified Base64 for
(variant 1, non standard)
No (variable)
(language/system-dependent)
Modified Base64 for
(variant 2, non standard)
No (variable)
(language/system-dependent)
Non-standard -safe Modification of Base64 used in
No (variable)
(application-dependent)
The first known standardized use of the encoding now called MIME Base64 was in the
(PEM) protocol, proposed by
in 1987. PEM defines a "printable encoding" scheme that uses Base64 encoding to transform an arbitrary sequence of
to a format that can be expressed in short lines of 6-bit characters, as required by transfer protocols such as .
The current version of PEM (specified in ) uses a 64-character alphabet consisting of upper- and lower-case
(A–Z, a–z), the numerals (0–9), and the "+" and "/" symbols. The "=" symbol is also used as a special suffix code. The original specification, , additionally used the "*" symbol to delimit encoded but unencrypted data within the output stream.
To convert data to PEM printable encoding, the first byte is placed in the
eight bits of a 24-bit , the next in the middle eight, and the third in the
eight bits. If there are fewer than three bytes left to encode (or in total), the remaining buffer bits will be zero. The buffer is then used, six bits at a time, most significant first, as indices into the string: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz+/", and the indicated character is output.
The process is repeated on the remaining data until fewer than four octets remain. If three octets remain, they are processed normally. If fewer than three octets (24 bits) are remaining to encode, the input data is right-padded with zero bits to form an integral multiple of six bits.
After encoding the non-padded data, if two octets of the 24-bit buffer are padded-zeros, two "=" characters are ap if one octet of the 24-bit buffer is filled with padded-zeros, one "=" character is appended. This signals the decoder that the zero bits added due to padding should be excluded from the reconstructed data. This also guarantees that the encoded output length is a multiple of 4 bytes.
PEM requires that all encoded lines consist of exactly 64 printable characters, with the exception of the last line, which may contain fewer printable characters. Lines are delimited by whitespace characters according to local (platform-specific) conventions.
(Multipurpose Internet Mail Extensions) specification lists Base64 as one of two
schemes (the other being ). MIME's Base64 encoding is based on that of the
version of PEM: it uses the same 64-character alphabet and encoding mechanism as PEM, and uses the "=" symbol for output padding in the same way, as described at .
MIME does not specify a fixed length for Base64-encoded lines, but it does specify a maximum line length of 76 characters. Additionally it specifies that any extra-alphabetic characters must be ignored by a compliant decoder, although most implementations use a CR/LF
pair to delimit encoded lines.
Thus, the actual length of MIME-compliant Base64-encoded binary data is usually about 137% of the original data length, though for very short messages the overhead can be much higher due to the overhead of the headers. Very roughly, the final size of Base64-encoded binary data is equal to 1.37 times the original data size + 814 bytes (for headers). The size of the decoded data can be approximated with this formula:
bytes = (string_length(encoded_string) - 814) / 1.37
, described first in , which was later superseded by , introduced a system called modified Base64. This data encoding scheme is used to encode
characters for use in 7-bit transports such as . It is a variant of the Base64 encoding used in MIME.
The "Modified Base64" alphabet consists of the MIME Base64 alphabet, but does not use the "=" padding character. UTF-7 is intended for use in mail headers (defined in ), and the "=" character is reserved in that context as the escape character for "quoted-printable" encoding. Modified Base64 simply omits the padding and ends immediately after the last Base64 digit containing useful bits leaving up to three unused bits in the last Base64 digit.
, described in , describes Radix-64 encoding, also known as "ASCII Armor". Radix-64 is identical to the "Base64" encoding described from MIME, with the addition of an optional 24-bit . The
is calculated on the input
the checksum is then encoded with the same Base64 algorithm and, prefixed by "=" symbol as separator, appended to the encoded output data.
, entitled The Base16, Base32, and Base64 Data Encodings, is an informational (non-normative) memo that attempts to unify the
specifications of Base64 encodings, alternative-alphabet encodings, and the seldom-used Base32 and Base16 encodings.
Unless implementations are written to a specification that refers to
and specifically requires otherwise,
forbids implementations from generating messages containing characters outside the encoding alphabet or without padding, and it also declares that decoder implementations must reject data that contain characters outside the encoding alphabet.
This RFC obsoletes
and focuses on Base64/32/16:
This document describes the commonly used Base64, Base32, and Base16 encoding schemes. It also discusses the use of line-feeds in encoded data, use of padding in encoded data, use of non-alphabet characters in encoded data, use of different encoding alphabets, and canonical encodings.
Another variant called modified Base64 for filename uses '-' instead of '/', because Unix and Windows filenames cannot contain '/'.
It could be recommended to use the modified Base64 for URL instead, since then the filenames could be used in URLs also.
Base64 encoding can be helpful when fairly lengthy identifying information is used in an HTTP environment. For example, a database persistence framework for
objects might use Base64 encoding to encode a relatively large unique id (generally 128-bit ) into a string for use as an HTTP parameter in HTTP forms or HTTP GET . Also, many applications need to encode binary data in a way that is convenient for inclusion in URLs, including in hidden web form fields, and Base64 is a convenient encoding to render them in a compact way.
Using standard Base64 in
requires encoding of '+', '/' and '=' characters into special
hexadecimal sequences ('+' becomes '%2B', '/' becomes '%2F' and '=' becomes '%3D'), which makes the string unnecessarily longer.
For this reason, modified Base64 for URL variants exist, where the '+' and '/' characters of standard Base64 are respectively replaced by '-' and '_', so that using
is no longer necessary and have no impact on the length of the encoded value, leaving the same encoded form intact for use in relational databases, web forms, and object identifiers in general. Some variants allow or require omitting the padding '=' signs to avoid them being confused with field separators, or require that any such padding be percent-encoded. Some libraries will encode '=' to '.'.
There are other variants that use _- or ._ when the Base64 variant string must be used within valid identifiers for programs.
identifiers and name tokens are encoded using two variants:
.- for use in
name tokens (:AAEFhjC13WlPEA568vDUBJRdwzSt56tG3Xc), or even
_: for use in more restricted XML identifiers (TonyduongBot).
The atob() and btoa() JavaScript methods, defined in the HTML5 draft specification, provide Base64 encoding and decoding functionality to web pages. The btoa() method outputs padding characters, but these are optional in the input of the atob() method.
containing embedded JPEG images encoded in Base64
Base64 can be used in a variety of contexts:
Base64 can be used to transmit and store text that might otherwise cause
use Base64 to evade basic
tools, which often do not decode Base64 and therefore cannot detect keywords in encoded messages.
Base64 is used to encode character strings in
Base64 is often used to embed binary data in an
file, using a syntax similar to &data encoding="base64"&…&/data& e.g.
in 's exported bookmarks.html.
Base64 is used to encode binary files such as images within scripts, to avoid depending on external files.
can use Base64 to represent file contents. For instance, background images and fonts can be specified in a
stylesheet file as data: URIs, instead of being supplied in separate files.
The FreeSWAN ipsec implementation precedes Base64 strings with 0s, so they can be distinguished from text or hexadecimal strings.
Although not part of the official specification for SVG, some viewers can interpret Base64 when used for embedded elements, such as images inside SVG.
, traditionally used on , uses ASCII 32 (" " (space)) through 95 ("_"), consecutively, making its 64-character set " !"#$%&'()*+,-./:;&=&?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_". Avoiding all lower-case letters was helpful because many older printers only printed uppercase. Using consecutive ASCII characters saved computing power because it was only necessary to add 32, not do a lookup. Its use of most punctuation characters and the space character limits its usefulness.[]
(HQX), which was used within the , uses a different set of 64 characters. It uses upper and lower case letters, digits, and punctuation characters, but does not use some visually confusable characters like '7', 'O', 'g' and 'o'. Its 64-character set is "!"#$%&'()*+,-@ABCDEFGHIJKLMNPQRSTUVXYZ[`abcdefhijklmpqr".
Several other applications use radix-64 sets more similar to but in a different order to the Base64 format, starting with two symbols, then numerals, then uppercase, then lowercase:
Unix stores password hashes computed with
using radix-64 encoding called B64. It uses a mostly-alphanumeric set of characters, plus . and /. Its 64-character set is "./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz". Padding is not used.
5.5 standard for genealogical data interchange encodes multimedia files in its text-line hierarchical file format using radix-64. Its 64-character set is also ./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".
uses a mostly-alphanumeric character set similar to crypt and GEDCOM, but using + and - rather than . and /. Its 64-character set is "+-ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".
6PACK, used with some , uses a different set of 64 characters.
(also called Base85)
for a comparison of various encoding algorithms
. . October 2006. :. RFC 4648. .
. . February 1993. :. RFC 1421. .
. . November 1996. :. RFC 2045. .
. . July 2003. :. RFC 3548. .
. YUIBlog.
. . February 1987. :. RFC 989. .
. . July 1994. :. RFC 1642. .
. . May 1997. :. RFC 2152. .
. . November 2007. :. RFC 4880. .
. HTML 5.2 Editor's Draft.
2017. Introduced by , .
&image xlink:href="data:image/base64,JPEG contents encoded in Base64" ... /&
JSFiddle. . jsfiddle.net.
. Homepages.rootsweb.ancestry.com.
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