Errata

Many thanks to everyone who has submitted corrections! Your names now appear in the acknowledgements of current printings of the textbook.

Most Recent Errors (fixed 2010/09/02):

NOTE: All errors listed below have been fixed as of September 2, 2010. Any copies of the textbook ordered from Lulu after that time will not contain the errors below.

• p4 (Prof. Dale Skrien, Colby College) - The third byte of the IP Address in Figure 1.1 should have the binary value 00100010 (i.e. decimal value 34) instead of 00001010 (i.e. decimal value 10).
• p8 (Dr. Herman Koppelman, Open Universiteit, Netherlands) - HTTP stands for HyperText Transfer Protocol.
• p27 (Benson Limketkai, University of Washington) - The last sentence on the page should read, "We'll learn how to set elements' margins in Chapter 4 to place arbitrary blank space between paragraphs."
• p42 (Prof. Dale Skrien, Colby College) - Self-Check 6 should have the following code snippet below it:

  <ul>
    <li>Over 100 million copies:
  	<ul>
  	  <li>Michael Jackson: Thriller</li>
  	</ul>
    </li>
    <li>40-49 million copies:</li>
  	<ul>
  	  <li>AC/DC: Back in Black</li>
  	  <li>Eagles: Their Greatest Hits (1971-1975)</li>
  	  <li>Whitney Houston / Various artists: The Bodyguard</li>
  </ul>
  

• p61 (Prof. Dale Skrien, Colby College) - The last word in the third paragraph should be medium instead of large.
• p62 (Dr. Jamil Saquer, Missouri State University) - The last line in the last paragraph on page 62 should revised as follows: The order of values in list is important. Font style and weight must be first (in either order), followed by font size (second to last), and finally the list of font names.
• p106-107 (Benson Limketkai, University of Washington) - Examples 4.23 and 4.24 both should not use a "spacer" div.
• p107 (Benson Limketkai, University of Washington) - In Example 4.24, the class should be main, not urgent.
• p112 (Benson Limketkai, University of Washington) - In Example 4.28, the border style of the paragraph should be dashed.
• p130 (Benson Limketkai, University of Washington) - In Figure 4.20, the News list doesn't have the styles and formatting that were applied to it in the previous sections.
• p163 - In the code for the print_separated function, the variable $sep should be $separator .
• p169 (Prof. Dale Skrien, Colby College) - The first sentence (which starts at the end of p168) states that the count function returns 1 more than the highest occupied index in the array for arrays with non-consecutive indexes (like $autobots in the example on p168). This is incorrect. count strictly counts how many elements are in an array regardless of whether or not the indexes are consecutive.
• p171 (Steven Pell, UW student) - Both Example 5.60 and 5.61 pass a variable named $max to the max function. The first variable passed to the max function in both of these examples should be $largest instead.

  Additionally, the last sentence on this page reads "...adjust the value of $max, it would have changed $max's value...". It should say "...adjust the value of $num, it would have changed $num's value...".

• p173 (Prof. Dale Skrien, Colby College) - Example 5.64 should call implode("", $lines) instead of implode("\n", $lines) in order to avoid double spacing as the PHP file function preserves the newline characters (i.e. \n) at the end of each line.
• p174 (Benson Limketkai, University of Washington) - The last line of text should say that the code reverses the order of lines of all .txt files.
• p175 (Kristi Nguyen, UW student) - The last sentence of the fifth paragraph should end with, "calling file("example1.txt") would fail".
• p191 (Benson Limketkai, University of Washington) - The type attribute is not required on the input tag. (Its default value is text.)
• p219 (Dr. Jeffrey Lehman, Huntington University) - In the code for Example 6.37, a square bracket should be a parenthesis. The line should say if (is_uploaded_file($_FILES["pic"]["tmp_name"])) { .
• p252 - The last sentence in the last paragraph on this page should read, "As shown in the screenshot, JavaScript appears to have some serious math issues: It reports that 6 plus 7 equals 67!"
• p260 (Dr. Jeffrey Lehman, Huntington University) - In the code for Self Check 7.11, problem (h) refers to a non-existent function Math.log10. It should say, 100 + Math.floor(41.1 + 1.7) . The answer to the problem is 142.
• p307 (Benson Limketkai, University of Washington) - In the second line of the last paragraph, the class used is clickedbutton, not urgent.
• p313 (Kristi Nguyen, UW student) - In the for loop of Example 8.31, footerParas.length should be footerParagraphs.length.
• p315 (Benson Limketkai, University of Washington) - In the large paragraph, the text should read, "Example 8.34 shows the complete JavaScript code for the page and the resulting appearance in the browser after searching for a given string. Figure 8.6 shows the resulting appearance in the browser after searching for a given string."
• p320 (Albert Lui, UW student) - The third sentence in the second paragraph should say "...value between 0 and 650, and a random...".
• p351 (Prof. Dale Skrien, Colby College) - Example 9.29's form tag should be using the action attribute in place of the target attribute.
• p352 - The last paragraph should read, "One problem with our code is that it disallows all key presses other than ..."
• p353 (Prof. Dale Skrien, Colby College) - Example 9.33's form tag should be using the action attribute in place of the target attribute.
• p381 (Prof. Dale Skrien, Colby College) - Example 10.9's line of code that attaches its event handler should not accept any ajax parameter. It should read:

  ajax.onreadystatechange = function(ajax) {

• p435 (Prof. Dale Skrien, Colby College) - The output in Example 11.38 does not match the PHP code. The query should be:

  $query = "SELECT name, year FROM movies WHERE name LIKE Fight Club;";

• p437 (Kristi Nguyen, UW student) - mysql_free_resource should be mysql_free_result.
• p448 (Andy Simmons, Huntington University) - in code Example 11.48, the text:

  <title>Developing World Adventure Recommendertitle>
  

  should read:

  <title>Developing World Adventure Recommender</title>
  

• p525 (Prof. Dale Skrien, Colby College) - In table A.9, for the FLOAT(M, D) datatype, the table reads "Decimal precision can go to 24 places for a FLOAT". This is incorrect. The FLOAT data type is limited to 24 bits of precision or 7 decimal places of precision.

Minor/Typographical Errors:

• p2 (Sylvia Tashev, UW student) - In the first paragraph, missing the word "of" in the sentence: "A basic understanding {of} how..."
• p3 (Sylvia Tashev, UW student) - At the very bottom, missing the word "at": "In this section we'll look briefly {at} the last three of these layers..."
• p4 (Prof. Dale Skrien, Colby College) - The last line in the second paragraph reads "...8 bits of binary data can represent 28 = 256 different unique integers...". It should say "...8 bits of binary data can represent 2⁸ = 256 different unique integers...".
• p7 (Sylvia Tashev, UW student) - In paragraph four, missing "a": "As you know, users connect to {a} web server using..."
• p15 (Sylvia Tashev, UW student) - In the first paragraph, the sentence "The task of describing ..... are handled by...." does not have proper subject-verb agreement.
• p16 (Sylvia Tashev, UW student) - In paragraph three, "a" should be "an" in the sentence: "Most tags come in pairs, with {an} opening tag..."
• p24 (Steven Pell, UW student) - In the second to last paragraph, the sentence should say "The browser looks for the file smiley.gif in the images/ subdirectory...".
• p26 (Sylvia Tashev, UW student) - In the second paragraph missing "used" in the sentence: "... tags aren't just used to indicate formatting; they are {used} to specify the semantics..."
• p29 (Sylvia Tashev, UW student) - In question 4 - the word "and" should be "an": "What is the difference between {an} element and an attribute."
• p30 (Benson Limketkai, University of Washington) - In Example 2.19, the country Namibia is misspelled.
• p32 (Steven Pell, UW student) - The sentence above Example 2.22 should say, "Example 2.22 demonstrates a nested list.".
• p33 (Sylvia Tashev, UW student) - In Example 2.23, the list items in the nested unordered lists should be indented for good style.
• p39 (Sylvia Tashev, UW student) - In Example 2.29 the code doesn't appear to match the output. In particular it says this: "search?q=marty+stepp&ie=utf-8" But the "+stepp" and the "8" are missing in the output.
• p41 (Sylvia Tashev, UW student) - In the first paragraph missing the word "a" in the sentence "By default, when rendering contents of {a} pre element,..."
• p45 (Steven Pell, UW student) - In the second sentence of the second paragraph "complaint browser" should be "compliant browser".
• p55 (Steven Pell, UW student) - In the third sentence of the second paragraph "...h the same selector, the latter'..." should be in the same font as the rest of the paragraph (the font should not be larger in size).
• p56 (Sylvia Tashev, UW student) - In paragraph 3, don't need "are" in the sentence: "Table 3.1 lists the standard color names {are} recognized by all modern browsers." (Or maybe it should be "that are".)
• p57 (Sylvia Tashev, UW student) - In the first paragraph missing "to" in the sentence: "use hexadecimal codes {to} specify the red, green..."
• p66 (Sylvia Tashev, UW student) - In the first paragraph "to have" should be removed: "It is possible to have {to have} two style rules..."
• p67 (Prof. Dale Skrien, Colby College) - The first paragraph should end with, "to that particular heading".
• p71 (Prof. Dale Skrien, Colby College) - The third sentence of the second paragraph should say, "This option is supported by all browsers.".
• p71 (Steven Pell, UW student) - In the sixth sentence of the second paragraph, "one fail swoop" should be, "one fell swoop".

• p77 (Sylvia Tashev, UW student) - At the very bottom there appears to be an extra space in "H TML".
• p92 (Sylvia Tashev, UW student) - In the last sentence, "layout" should be plural (I think?): "Figure 4.3 illustrates various {layouts} of block elements..."
• p99 (Sylvia Tashev, UW student) - In Self-Check 4 the word "to" should not be there: "If you specify for an element {to} width of 10em..."
• p99 (Steven Pell, UW student) - In the first sentence the extra s should be removed: "Firebug is s a wonderful tool for web development."
• p103 (Sylvia Tashev, UW student) - In the bottom paragraph it says that "The effect of clear is that the element with a float setting will appear below any previous floating content, rather than side-by-side." However, shouldn't it be the element with the "clear" that will appear below?
• p110 (Sylvia Tashev, UW student) - Under the first bullet point of Inline Elements, the word "with" (or something like that) is missing: "...except when used {with} the img element."
• p147 (Sylvia Tashev, UW student) - At the very bottom it says "PHP supports storing the result of an expression into a variable for storing the results of evaluated expressions." Half the sentence is redundant of the other half.
• p150 (Kristi Nguyen, UW student) - The first sentence of the third paragraph should be in the same font as the rest of the paragraph (the font should not be larger in size).
• p158 (Sylvia Tashev, UW student) - In the last paragraph "the error" does not seem like it should be there:"... which is not usually {the error} where the missing brace needs to be inserted."
• p162 (Sylvia Tashev, UW student) - In the third paragraph it says "For example, to call the quadratic function we just declared..." However, the function just declared in the previous example is actually the slope equation.
• p190 (Sylvia Tashev, UW student) - The very last sentence on the page is missing its start: "{Table 6.1} summarizes the key attributes of the input element."
• p195 (Sylvia Tashev, UW student) - In the first paragraph, in sentence two, the word "that" is missing: "Checkboxes {that} are not checked are not included in the URL."
• p198 (Sylvia Tashev, UW student) - At the top, under bullet point three, the word "the" is missing: "... thus confirming {the} choice to the user."
• p201 (Sylvia Tashev, UW student) - In the third to last sentence, the word "of" is extra: "One way to do this is to use the fieldset and legend elements to group {of} related controls with an optional caption." Also the word "legend" should have the special bolded style. The last sentence also says "field set and legend"... and perhaps those should have that bolded style too and fieldset should be one word.
• p202 (Sylvia Tashev, UW student) - In the last paragraph, the word "the" is possibly missing: "We are not going to go into all of {the} details about styling controls here..."
• p207 (Kristi Nguyen, UW student) - The example at the top of the page is missing a caption. It should have a caption of, "Example 6.20 Hidden input parameters".
• p209 (Sylvia Tashev, UW student) - Missing "in": But {in} the forms that submit meal preferences or credit card information, presumably that information is meant to be saved by the server, so it should be sent as a POST."
• p239 (Kristi Nguyen, UW student) - The second sentence of the third paragraph should begin, "One of these is...".
• p243 (Sylvia Tashev, UW student) - In paragraph five, the word "a" is missing: "To assign a different value to {a} variable later..."
• p252 (Sylvia Tashev, UW student) - In paragraph two the last sentence is missing its beginning: "{Example 7.19} shows the relevant HTML code..."
• p253 (Sylvia Tashev, UW student) - In the box describing the parseFloat function the "an" should be an "a": "Converts a value into {a} real number and returns the number."
• p255 (Sylvia Tashev, UW student) - In the last paragraph, the word "the" is missing: "In addition to accessing characters through {the} charAt method..."
• p258 (Sylvia Tashev, UW student) - In the last paragraph, sentence two, a word is missing: "The place where you'll potentially {encounter} them is when your code has a bug."
• p264 (Sylvia Tashev, UW student) - In the next to last line the word "a" is extra or another word is missing: "... assign a variable a value if and only if it is {a} valid (not null, undefined, or some other falsey value) when otherwise..."
• p270 (Sylvia Tashev, UW student) - In the third example, in the second comment it says that the two elements being added are "Bebop" and "Rocksteady" however the example show it is "Bebop" and "Krang".
• p277 (Sylvia Tashev, UW student) - Very first line, a word is missing: "Let's also {add} some CSS..."
• p277 (Sylvia Tashev, UW student) - In the next sentence the word "to" seems to be extra: "We'll center the content on the page and {to} give the word clue a large Courier font with a bit of padding."
• p280 (Sylvia Tashev, UW student) - In the middle paragraph the verb "adds" does not agree: "Our guessLetter function will fetch.... and {add} it to...."
• p291 (Sylvia Tashev, UW student) - In the first paragraph, missing "a" in the sentence: "we are working on {a} Windows machine in a Netscape (Firefox) browser."
• p291 (Prof. Dale Skrien, Colby College) - The last sentence of the first paragraph should begin with, "...the browser would load kayak.com...".
• p309 (Prof. Dale Skrien, Colby College) - The last sentence of the third paragraph says "Figure 8.3 displays a short web page and a diagram of its resulting DOM tree.". It should be clarified that the tree in Figure 8.3 only shows the resulting DOM tree's element nodes (i.e. it doesn't include the attribute and text nodes that the actual DOM tree contains).
• p317 (Prof. Dale Skrien, Colby College) - The function in Example 8.36 should be more appropriately named addParagraphClick instead of addHeadingClick.
• p318 (Sylvia Tashev, UW student) - At the end of the first paragraph "use" should be "user": "The page will also have buttons allowing the {user} to add a single square..."
• p326 (Sylvia Tashev, UW student) - Under the references section, are the second level bullet points supposed to be a), b), c) or just empty circles like it is in the other chapters?
• p329 (Sylvia Tashev, UW student) - In the first paragraph, some word perhaps "library" is missing: "But first you must download the Prototype {library} to your own computer..."
• p337 (Sylvia Tashev, UW student) - In Table 9.8 the description for the up() function says that "if no selector is given all descendants are considered." Descendants should probably be ancestors.
• p348 (Sylvia Tashev, UW student) - In the next to last paragraph the word "square" should be plural: "This does cause {squares} to move on the page when we test it."
• p350 (Kristi Nguyen, UW student) - In Table 9.18, for the keyCode property, the description should read "(convert to a character...)".
• p356 (Sylvia Tashev, UW student) - In the first paragraph, missing "a": "...right clicking an image gives {a} context menu with an option to..."
• p358 (Kristi Nguyen, UW student) - The fourth sentence in the first paragraph should begin, "The call doesn't cause your page to halt".
• p372 (Kristi Nguyen, UW student) - The first sentence in the second paragraph should read "in a pleasant and useful way".
• p377 (Sylvia Tashev, UW student) - At the end of paragraph two, the word "to" is missing: "it can be a bit of work {to} extract meaningful information from plain text..."
• p388 (Sylvia Tashev, UW student) - On the first line "completely" should be "completed": "So far we have {completed} the first three steps..."
• p389 (Sylvia Tashev, UW student) - In paragraph four the word "uses" should be singular: "Apps called 'web services' {use} XML to..."
• p397 (Sylvia Tashev, UW student) - Example 10.30 does not show the year of the book in the output even though the code specifies it should be there.
• p403 (Sylvia Tashev, UW student) - In Example 10.36 the keyword "function" appears at the end of the comment instead of on the next line before the function name.
• p420 (Kristi Nguyen, UW student) - The first sentence of the last paragraph should begin, "You can use * as a wildcard to specify to all columns ...".
• p425 (Kristi Nguyen, UW student) - The third sentence of the first paragraph should begin, "You can do this by using by sequencing a number of different predicates together ...".
• p428 (Sylvia Tashev, UW student) - Missing "to" in the sentence: "The DELETE statement shown in Example 11.25 is used {to} delete rows from a database table."
• p432 (Sylvia Tashev, UW student) - In the next to last paragraph the third sentence should start with "If {there} was an error..."
• p436 (Sylvia Tashev, UW student) - In the next to last paragraph a verb is not correct; it should be: "... anything to the left of or is executed before {evaluating} the right operand."
• p437 (Sylvia Tashev, UW student) - In Table 11.6 the Description of mysql_ping is missing the verb "is": "Checks to see whether or not a database connection {is} working..."
• p438 (Sylvia Tashev, UW student) - Under 11.4.1 the fourth sentence is missing the word "the": "... the number of rows returned will be {the} product of..."
• p444 (Sylvia Tashev, UW student) - In question 23 "their" should be "there" in "Is {there} anything wrong with it?"
• p446 (Sylvia Tashev, UW student) - In step 7 missing the word "to": "write PHP functions {to} retrieve the..."
• p451 (Sylvia Tashev, UW student) - In the second paragraph the first "writing" probably shouldn't be there: "Again, we begin {writing} by writing the..."
• p451 (Sylvia Tashev, UW student) - In the third paragraph the first "the" shouldn't be there and the verb "decide" should be in the past tense: "Since {the} both the index and results pages have the same HTML to declare the page and show the logo, we have {decided} to make a shared file..."
• p457 (Sylvia Tashev, UW student) - Under bullet point 2 it seems like the word "where" should be "with" because otherwise the sentence sounds strange: "tables {with} columns that..."
• p457 (Sylvia Tashev, UW student) - Under bullet point 9, perhaps "object" should be plural: "those {objects} and attributes are mapped..."
• p460 (Sylvia Tashev, UW student) - At the very top line there is an extra "is": "there is an entire field of computer science {is} devoted to the interaction between computers and people..."
• p466 (Sean McGuire, UW student) - The second sentence of the last paragraph should read, "Just as people don't like to fill out paperwork, people don't like to fill out online forms."
• p467 (Sylvia Tashev, UW student) - Under "Multiple Choice" a word seems to be missing after "multiple": "User is to select multiple {...what?} from several choices."
• p468 (Sylvia Tashev, UW student) - In the second paragraph "visually" is the wrong form of the word: "Users with {visual} impairments...."
• p471 (Sean McGuire, UW student) - The text "(output goes here)" should be removed.
• p473 (Sean McGuire, UW student) - The second sentence of the fourth paragraph should read, "Table 12.4 below below lists several of the more commonly used options and their descriptions."
• p476 (Sylvia Tashev, UW student) - At the very bottom, the "Error! Reference source not found." should say "Table 12.8".
• p477 (Sylvia Tashev, UW student) - In the first paragraph "an" should not be there in the sentence: "... but img elements have {an} implicitly defined heights and widths."
• p478 (Sylvia Tashev, UW student) - In Example 12.14 the selector should be the id "dollbody" and not "dollbase".
• p484 (Sylvia Tashev, UW student) - In bullet point five "places" should be singular: "... alternate text in {place} of any images and multimedia..."
• p493 (Sylvia Tashev, UW student) - In the last paragraph, the word "as" is missing: "The last, most common type of hosting... is known {as} collocation."
• p495 (Sylvia Tashev, UW student) - On line two the first "include" should be removed: "... but web hosting does not {include} always include a domain name..."
• p505 (Sylvia Tashev, UW student) - In the second paragraph the word "ever" should be "even": "...or maybe {even} from news sites that are interested in your web site..."
• p506 (Sylvia Tashev, UW student) - In paragraph three at the end of the first line "been" should be "be": "SEO should always {be} in mind when..."
• p511 (Sylvia Tashev, UW student) - In the box the word "bottled" should be "bottle": "a link to wine.com to purchase the described {bottle}."
• p517 (Sylvia Tashev, UW student) - At the end of bullet point eight it should either say "to make money" or "to be profitable".
• p519 (Prof. Dale Skrien, Colby College) - The third bullet should say, "the data type of each column, and whether the column allows NULL values".
• p520 (Sylvia Tashev, UW student) - At the end of the first paragraph in the middle section "countries" should be "country's" in the sentence: "...storing information about each {country's} government..."
• p520 (Sylvia Tashev, UW student) - In the following paragraph the word "can" should be omitted: "In order to {can} train its volunteers properly..."
• p521 (Prof. Dale Skrien, Colby College) - The second to last sentence in the first paragraph says "...we consider continent an entity.". It should say "...we consider continent an attribute."
• p522 (Greg Stallings, UW student) - The second sentence in the second paragraph reads, "There are several of kinds of relationships...". It should say, "There are several kinds of relationships..."
• p522 (Greg Stallings, UW student) - The first sentence of the third paragraph should read, "Now to the relationships that involving countries and languages."
• p523 (Sylvia Tashev, UW student) - In the next to last line the word "design" is probably missing: "It is not uncommon for those who don't have much experience with relational database {design} to create a database that stores information like in Table A.7"
• p524 (Prof. Dale Skrien, Colby College) - The "is" after the middle table should say, "All tables in the world database schema proposed in Table A.5 is are in Third Normal Form...".
• p524 - The first sentence of the third paragraph should read, "A table is at the third level of normalization, also called Third Normal Form, ...".
• p524 (Greg Stallings, UW student) - The parenthetical after the second to last sentence in the third paragraph should begin, "(Codd is invented ...".
• p526 (Sylvia Tashev, UW student) - In the second line either "a" is missing or "field" should be plural: "... how data types for a {field} should be chosen."
• p526 (Sylvia Tashev, UW student) - In the third line the word "is" is missing somewhere in the sentence: "... we ask Ayuda what {is} the longest name..."
• p526 (Sylvia Tashev, UW student) - Under Final World Schema it has a sentence which lists two tables. The first one should be Table A.10.

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