bitbybitbook.com Bitbybitbook.com

   
Bit By Bit: Social Research in the Digital Age

Domain Summary

What is the traffic rank for Bitbybitbook.com?

• Bitbybitbook.com ranks #4,824,093 globally on HypeStat.

What percent of global Internet users visit Bitbybitbook.com?

2.07E-5% of global Internet users visit Bitbybitbook.com

How many people visit Bitbybitbook.com each day?

• Bitbybitbook.com receives approximately 1K visitors and 347 page impressions per day.

Which countries does Bitbybitbook.com receive most of its visitors from?

• Bitbybitbook.com is mostly visited by people located in United States,Colombia,Uruguay.

How much Bitbybitbook.com can earn?

• Bitbybitbook.com should earn about $1.26/day from advertising revenue.

What is Bitbybitbook.com estimated value?

• Estimated value of Bitbybitbook.com is $1,216.24.

What IP addresses does Bitbybitbook.com resolve to?

• Bitbybitbook.com resolves to the IP addresses 185.199.111.153.

Where are Bitbybitbook.com servers located in?

• Bitbybitbook.com has servers located in California, United States.

bitbybitbook.com Profile

Title:Bit By Bit: Social Research in the Digital Age Description:Bit by Bit: Social Research in the Digital Age by Matthew J Salganik. This book is for social scientists who want to do more data science, and data scientists who want to do more social science.
Category:Science and Education / Social Sciences

What technologies does bitbybitbook.com use?

These are the technologies used at bitbybitbook.com. bitbybitbook.com has a total of 5 technologies installed in 5 different categories.

bitbybitbook.com Traffic Analysis

Bitbybitbook.com is ranked #4,824,093 in the world. This website is viewed by an estimated 1K visitors daily, generating a total of 347 pageviews. This equates to about 30.9K monthly visitors. Bitbybitbook.com traffic has increased by 1123.3% compared to last month.
Daily Visitors1K
547.16%
Monthly Visits30.9K
1123.3%
Pages per Visit0.34
590%
Visit duration01:23
Bounce Rate74.39%
54.11%
Is this your site?Verify your site's metrics.
Daily Unique Visitors:
1,019
Monthly Visits:
30,876
Pages per Visit:
0.34
Daily Pageviews:
347
Avg. visit duration:
01:23
Bounce rate:
74.39%
Global Reach:
2.07E-5%
Monthly Visits (SEMrush):
2,153
Monthly Unique Visitors (SEMrush):
1,139
Monthly Visits (SimilarWeb):
30,255
HypeRank:
4,824,093
SEMrush Rank:
2,180,557
SimilarWeb Rank:
3,836,100
*All traffic values are estimates only.

Traffic sources

Direct:
100.00%
Referral:
0%
Search:
0%
Social:
0%
Paid:
0%

Desktop vs Mobile

Desktop:
100.00%
Mobile:
0%

Total Visits Last 3 Months

23.8K
JUL
2.5K
AUG
30.9K
SEP

Visitors by country

Country
Users%
 
United States 5.84%
 
Colombia 3.75%
 
Uruguay 3.55%
 
Turkey 3.39%
 
Russian Federation 2.87%

 

SEMrush is a complete on line advertising and marketing platform that gives a extensive variety of gear and functions to help companies and entrepreneurs in enhancing their on line visibility and optimizing their virtual advertising and marketing strategies.
SemRushSemRush
Domain:
  bitbybitbook.com
Rank:
(Rank based on keywords, cost and organic traffic)
  2,180,557
Organic Keywords:
(Number of keywords in top 20 Google SERP)
  380
Organic Traffic:
(Number of visitors coming from top 20 search results)
  226
Organic Cost:
((How much need to spend if get same number of visitors from Google Adwords)
  $76.00

Which sites are competitors to bitbybitbook.com?

Websites similar to bitbybitbook.com are sites similar on user interests and browsing behavior. Users can discover new websites that are similar to the ones they already enjoy or find useful.
Last update was 832 days ago
     
This can take up to 60 seconds. Please wait...

*HypeStat.com is not promoting or affiliated with bitbybitbook.com in any way. Only publicly available statistics data are displayed.

Search Engine Indexes

Search engine indexes are huge databases or collections of net pages that search engines like google like google and yahoo use to retrieve applicable facts while customers carry out searches. These indexes are created through search engines like google and yahoo through crawling and indexing net pages from throughout the internet.
Google Index:
12,300
Bing Index:
2,160

Revenue report

Google.com would generate approximately $1.3 per day if the source of income were advertisements, which equates to an estimated monthly revenue of $37.8 and annual gross revenue of approximately $459.9. Based on these figures, the site's net worth is estimated at around $1.2K.

How much would bitbybitbook.com make?

Daily Revenue:
$1.26
Monthly Revenue:
$37.80
Yearly Revenue:
$459.90
*All earnings values are estimates only.

Daily earning by country

 
CountryPageviewsEarning
 
United States 20$0.10
 
Colombia 13$0.01
 
Uruguay 12$0.00
 
Russian Federation 10$0.00
 
Turkey 12$0.00

Loss of money due to Adblock?

Daily Revenue Loss:
$0.02
Monthly Revenue Loss:
$0.58
Yearly Revenue Loss:
$7.01
Daily Pageviews Blocked:
7
Monthly Pageviews Blocked:
224
Yearly Pageviews Blocked:
2,723

Daily revenue loss by country

 
CountryBlockedLost Money
 
United States 4$0.02
 
Colombia 1$0.00
 
Uruguay 1$0.00
 
Russian Federation 1$0.00
 
Turkey 1$0.00

How much is bitbybitbook.com worth?

Website Value:
$1.2K

Ad Experience Report

Summary of the ad experience rating of a website for a specific platform.

Mobile summary

Root domain:
bitbybitbook.com
Ad filtering:
(Chrome is not filtering ads on your site.)
Off
Status:
(The status of the site that is reviewed for the Better Ads Standards.)
Not reviewed

Desktop summary

Root domain:
bitbybitbook.com
Ad filtering:
(Chrome is not filtering ads on your site.)
Off
Status:
(The status of the site that is reviewed for the Better Ads Standards.)
Not reviewed

Abusive Experience Report

Summary of the abusive experience rating of a website.
Root domain:
bitbybitbook.com
Enforcement:
(Chrome is not preventing your site from opening new windows or tabs.)
Off
Status:
(The status of the site reviewed for the abusive experiences.)
Not reviewed

Where is bitbybitbook.com hosted?

Bitbybitbook.com may be hosted in multiple data centers distributed in different locations around the world. This is probably just one of them.
Server IP:
185.199.111.153
ASN:
AS54113 
ISP:
Fastly 
Server Location:
California, CA
United States, US
 

Other sites hosted on 185.199.111.153

How fast does bitbybitbook.com load?

The average loading time of bitbybitbook.com is 97 ms. The Desktop speed index is 99 and mobile speed index is 61.
Average Load Time:
97 ms

Page Speed (Google PageSpeed Insights) - Desktop

99
0-49 50-89 90-100 i

Field Data

Over the last 30 days, the field data shows that this page has a FAST speed compared to other pages in the Chrome User Experience Report.We are showing the 90th percentile of FCP and the 95th percentile of FID.

Cumulative Layout Shift (CLS)2ms Web Statistics and Analysis | HypeStat 90% Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 9%
Time To First Byte (TTFB)463ms Web Statistics and Analysis | HypeStat 89% Web Statistics and Analysis | HypeStat 6% Web Statistics and Analysis | HypeStat 3%
First Contentful Paint (FCP)981ms Web Statistics and Analysis | HypeStat 93% Web Statistics and Analysis | HypeStat 2% Web Statistics and Analysis | HypeStat 4%
First Input Delay (FID)0 Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 0%
Interaction To Next Paint (INP)0 Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 0%
Largest Contentful Paint (LCP)994ms Web Statistics and Analysis | HypeStat 93% Web Statistics and Analysis | HypeStat 6% Web Statistics and Analysis | HypeStat 0%

Origin Data

All pages served from this origin have an FAST speed compared to other pages in the Chrome User Experience Report. over the last 30 days.To view suggestions tailored to each page, analyze individual page URLs.

Cumulative Layout Shift (CLS)0ms Web Statistics and Analysis | HypeStat 96% Web Statistics and Analysis | HypeStat 2% Web Statistics and Analysis | HypeStat 1%
Time To First Byte (TTFB)186ms Web Statistics and Analysis | HypeStat 97% Web Statistics and Analysis | HypeStat 1% Web Statistics and Analysis | HypeStat 0%
First Contentful Paint (FCP)417ms Web Statistics and Analysis | HypeStat 98% Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 0%
First Input Delay (FID)3ms Web Statistics and Analysis | HypeStat 99% Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 0%
Interaction To Next Paint (INP)25ms Web Statistics and Analysis | HypeStat 99% Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 0%
Largest Contentful Paint (LCP)424ms Web Statistics and Analysis | HypeStat 99% Web Statistics and Analysis | HypeStat 0% Web Statistics and Analysis | HypeStat 0%

Lab Data

Timing budget  
Set a timing budget to help you keep an eye on the performance of your site. Performant sites load fast and respond to user input events quickly. Learn more about performance budgets
Lazy load third-party resources with facades  
Some third-party embeds can be lazy loaded. Consider replacing them with a facade until they are required. Learn how to defer third-parties with a facade
Total Blocking Time 0 ms
Sum of all time periods between FCP and Time to Interactive, when task length exceeded 50ms, expressed in milliseconds. Learn more about the Total Blocking Time metric
Has a `<meta name="viewport">` tag with `width` or `initial-scale`  
A `<meta name="viewport">` not only optimizes your app for mobile screen sizes, but also prevents . a 300 millisecond delay to user input Learn more about using the viewport meta tag
Max Potential First Input Delay 40 ms
The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric
Time to Interactive 0.6 s
Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric
Speed Index 0.6 s
Speed Index shows how quickly the contents of a page are visibly populated. Learn more about the Speed Index metric
Largest Contentful Paint 1.0 s
Largest Contentful Paint marks the time at which the largest text or image is painted. Learn more about the Largest Contentful Paint metric
First Contentful Paint 0.6 s
First Contentful Paint marks the time at which the first text or image is painted. Learn more about the First Contentful Paint metric
First Meaningful Paint 0.6 s
First Meaningful Paint measures when the primary content of a page is visible. Learn more about the First Meaningful Paint metric
Performance budget  
Keep the quantity and size of network requests under the targets set by the provided performance budget. Learn more about performance budgets

Page Speed (Google PageSpeed Insights) - Mobile

61
0-49 50-89 90-100 i

Field Data

Over the last 30 days, the field data shows that this page has a AVERAGE speed compared to other pages in the Chrome User Experience Report.We are showing the 90th percentile of FCP and the 95th percentile of FID.

Cumulative Layout Shift (CLS)0ms Web Statistics and Analysis | HypeStat 98% Web Statistics and Analysis | HypeStat 1% Web Statistics and Analysis | HypeStat 0%
Time To First Byte (TTFB)865ms Web Statistics and Analysis | HypeStat 72% Web Statistics and Analysis | HypeStat 19% Web Statistics and Analysis | HypeStat 7%
First Contentful Paint (FCP)1.6s Web Statistics and Analysis | HypeStat 78% Web Statistics and Analysis | HypeStat 12% Web Statistics and Analysis | HypeStat 9%
First Input Delay (FID)14ms Web Statistics and Analysis | HypeStat 95% Web Statistics and Analysis | HypeStat 3% Web Statistics and Analysis | HypeStat 1%
Interactive To Next Paint (INP)127ms Web Statistics and Analysis | HypeStat 91% Web Statistics and Analysis | HypeStat 7% Web Statistics and Analysis | HypeStat 1%
Largest Contentful Paint (LCP)1.6s Web Statistics and Analysis | HypeStat 88% Web Statistics and Analysis | HypeStat 6% Web Statistics and Analysis | HypeStat 5%

Origin Data

All pages served from this origin have an AVERAGE speed compared to other pages in the Chrome User Experience Report. over the last 30 days.To view suggestions tailored to each page, analyze individual page URLs.

Cumulative Layout Shift (CLS)0ms Web Statistics and Analysis | HypeStat 98% Web Statistics and Analysis | HypeStat 1% Web Statistics and Analysis | HypeStat 0%
Time To First Byte (TTFB)865ms Web Statistics and Analysis | HypeStat 72% Web Statistics and Analysis | HypeStat 19% Web Statistics and Analysis | HypeStat 7%
First Contentful Paint (FCP)1.6s Web Statistics and Analysis | HypeStat 78% Web Statistics and Analysis | HypeStat 12% Web Statistics and Analysis | HypeStat 9%
First Input Delay (FID)14ms Web Statistics and Analysis | HypeStat 95% Web Statistics and Analysis | HypeStat 3% Web Statistics and Analysis | HypeStat 1%
Interactive To Next Paint (INP)127ms Web Statistics and Analysis | HypeStat 91% Web Statistics and Analysis | HypeStat 7% Web Statistics and Analysis | HypeStat 1%
Largest Contentful Paint (LCP)1.6s Web Statistics and Analysis | HypeStat 88% Web Statistics and Analysis | HypeStat 6% Web Statistics and Analysis | HypeStat 5%

Lab Data

Time to Interactive 5.6 s
Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric
Largest Contentful Paint 3.8 s
Largest Contentful Paint marks the time at which the largest text or image is painted. Learn more about the Largest Contentful Paint metric
Performance budget  
Keep the quantity and size of network requests under the targets set by the provided performance budget. Learn more about performance budgets
Max Potential First Input Delay 380 ms
The maximum potential First Input Delay that your users could experience is the duration of the longest task. Learn more about the Maximum Potential First Input Delay metric
Lazy load third-party resources with facades  
Some third-party embeds can be lazy loaded. Consider replacing them with a facade until they are required. Learn how to defer third-parties with a facade
First Meaningful Paint 1.8 s
First Meaningful Paint measures when the primary content of a page is visible. Learn more about the First Meaningful Paint metric
Total Blocking Time 590 ms
Sum of all time periods between FCP and Time to Interactive, when task length exceeded 50ms, expressed in milliseconds. Learn more about the Total Blocking Time metric
Preload Largest Contentful Paint image  
If the LCP element is dynamically added to the page, you should preload the image in order to improve LCP. Learn more about preloading LCP elements
First Contentful Paint 1.8 s
First Contentful Paint marks the time at which the first text or image is painted. Learn more about the First Contentful Paint metric
Largest Contentful Paint image was not lazily loaded  
Above-the-fold images that are lazily loaded render later in the page lifecycle, which can delay the largest contentful paint. Learn more about optimal lazy loading
Speed Index 2.3 s
Speed Index shows how quickly the contents of a page are visibly populated. Learn more about the Speed Index metric
Timing budget  
Set a timing budget to help you keep an eye on the performance of your site. Performant sites load fast and respond to user input events quickly. Learn more about performance budgets
Has a `<meta name="viewport">` tag with `width` or `initial-scale`  
A `<meta name="viewport">` not only optimizes your app for mobile screen sizes, but also prevents . a 300 millisecond delay to user input Learn more about using the viewport meta tag

Does bitbybitbook.com use compression?

Website compression is the process of reducing the size of website files, such as HTML, CSS, JavaScript, and image files, to improve website performance and load times. Compressing website files can significantly reduce the amount of data that needs to be transferred from the server to the user's browser, resulting in faster page load times and improved user experience. Files on bitbybitbook.com are reduced by 72%.
bitbybitbook.com use gzip compression.
Original size: 24.55 KB
Compressed size: 6.63 KB
File reduced by: 17.92 KB (72%)

Google Safe Browsing

Google Safe Browsing is a service provided by Google that helps protect users from visiting websites that may contain malicious or harmful content, such as malware, phishing attempts, or deceptive software.
This site is not currently listed as suspicious

MyWot.com Reputation Ratings

MyWOT (short for "My Web of Trust") is a web-based reputation and rating service that provides users with information about the trustworthiness and safety of websites.
Status:
  SAFE

SSL Checker - SSL Certificate Verify

An SSL (Secure Sockets Layer) certificate is a digital certificate that establishes a secure encrypted connection between a web server and a user's web browser. It provides authentication and encryption, ensuring that data transmitted between the server and the browser remains private and protected. bitbybitbook.com supports HTTPS.
 bitbybitbook.com supports HTTPS
     
Verifying SSL Support. Please wait...
Common Name: www.bitbybitbook.com
Organization:
Location:
Issuer: R3
Valid from: Sep 30 11:57:41 2023 GMT
Valid until: Dec 29 11:57:40 2023 GMT
Authority: CA:FALSE
Keysize: 2048 Bits
Common Name: R3
Organization: Let's Encrypt
Location: US
Issuer: ISRG Root X1
Valid from: Sep 4 00:00:00 2020 GMT
Valid until: Sep 15 16:00:00 2025 GMT
Authority: CA:TRUE
Keysize: 2048 Bits
Common Name: ISRG Root X1
Organization: Internet Security Research Group
Location: US
Issuer: DST Root CA X3
Valid from: Jan 20 19:14:03 2021 GMT
Valid until: Sep 30 18:14:03 2024 GMT
Authority: CA:TRUE
Keysize: 4096 Bits

Verify HTTP/2 Support

HTTP/2 (Hypertext Transfer Protocol version 2) is a major revision of the HTTP protocol, which is the foundation of data communication on the World Wide Web. It was developed as an improvement over the previous HTTP/1.1 version to enhance web performance and efficiency.
 bitbybitbook.com supports HTTP/2
     
Verifying HTTP/2.0 Support. Please wait...

Http Header

HTTP headers are extra portions of records despatched among a consumer (which include an internet browser) and a server at some stage in an HTTP request or response. They offer instructions, metadata, or manipulate parameters for the conversation among the consumer and server.
server: GitHub.com
content-type: text/html
location: https://www.bitbybitbook.com/
x-github-request-id: 85CE:6E1A:1D226AE:273659E:653D37F9
accept-ranges: bytes
date: Sat, 28 Oct 2023 16:34:01 GMT
via: 1.1 varnish
age: 0
x-served-by: cache-chi-kigq8000127-CHI
x-cache: MISS
x-cache-hits: 0
x-timer: S1698510841.197486,VS0,VE22
vary: Accept-Encoding
x-fastly-request-id: 38c28fd47bed1b2b0cf499128e5923e518ef768b
content-length: 162

HTTP/2 200 
server: GitHub.com
content-type: text/html; charset=utf-8
x-origin-cache: HIT
last-modified: Mon, 11 Apr 2022 20:14:26 GMT
access-control-allow-origin: *
etag: W/"62548c22-6234"
expires: Sat, 28 Oct 2023 16:44:01 GMT
cache-control: max-age=600
content-encoding: gzip
x-proxy-cache: MISS
x-github-request-id: DADC:958D:1DF25B0:2812492:653D37F8
accept-ranges: bytes
date: Sat, 28 Oct 2023 16:34:01 GMT
via: 1.1 varnish
age: 0
x-served-by: cache-chi-klot8100163-CHI
x-cache: MISS
x-cache-hits: 0
x-timer: S1698510841.245888,VS0,VE25
vary: Accept-Encoding
x-fastly-request-id: 3d2e2982fa268721a7f534a14d4d275745b47c5f
content-length: 6789

DNS Lookup

DNS entries (Domain Name System) are a critical component of the Internet infrastructure. They act as directories that translate human-readable domain names (such as example.com) to machine-readable IP addresses. DNS records are stored on DNS servers and help forward internet traffic efficiently.
Type Ip Target/Txt TTL
TXT google-site-verification=hxL1z9ReF7jyMk61wQPPKU9az5t-8HcylaxanalDX1k 3600
TXT google-site-verification=QEm9oAMwpO8if0fWrCvbngZe6fOTeN8LkcNP8-qiXi8 3600
TXT v=spf1 include:_spf.google.com ~all 3600
MX alt1.aspmx.l.google.com 3600
MX aspmx.l.google.com 3600
MX aspmx3.googlemail.com 3600
MX aspmx2.googlemail.com 3600
MX alt2.aspmx.l.google.com 3600
SOA 3600
Mname ns23.domaincontrol.com
Rname dns.jomax.net
Serial Number 2018051403
Refresh 28800
Retry 7200
Expire 604800
Minimum TTL 3600
A 185.199.110.153 3551
A 185.199.109.153 3551
A 185.199.108.153 3551
A 185.199.111.153 3551
NS ns24.domaincontrol.com 3600
NS ns23.domaincontrol.com 3600

Whois Lookup

Domain WHOIS is a public database that provides information about domain names, including registered owners, contact information, domain registrars, registration and expiration dates, name servers, and other relevant information. Domain registration for this website began on April 27, 2012 and will expire on April 27, 2024 if not renewed. This website is now assigned through the registrar GoDaddy.com, LLC. The WHOIS data for this website's domain was last updated on April 28, 2023.
Domain Created:
2012-04-27
Domain Expires:
2024-04-27
Domain Updated:
2023-04-28
Domain Age:
13 years 9 months 9 days
Domain Registrar:
GoDaddy.com, LLC
Domain Owner:
Domains By Proxy, LLC
WhoIs:
 

Domain Name: BITBYBITBOOK.COM
Registry Domain ID: 1716416613_DOMAIN_COM-VRSN
Registrar WHOIS Server: whois.godaddy.com
Registrar URL: https://www.godaddy.com
Updated Date: 2023-04-28T07:22:09Z
Creation Date: 2012-04-27T08:31:52Z
Registrar Registration Expiration Date: 2024-04-27T08:31:52Z
Registrar: GoDaddy.com, LLC
Registrar IANA ID: 146
Registrar Abuse Contact Email: email
Registrar Abuse Contact Phone: +1.4806242505
Domain Status: clientTransferProhibited https://icann.org/epp#clientTransferProhibited
Domain Status: clientUpdateProhibited https://icann.org/epp#clientUpdateProhibited
Domain Status: clientRenewProhibited https://icann.org/epp#clientRenewProhibited
Domain Status: clientDeleteProhibited https://icann.org/epp#clientDeleteProhibited
Registry Registrant ID: Not Available From Registry
Registrant Name: Registration Private
Registrant Organization: Domains By Proxy, LLC
Registrant Street: DomainsByProxy.com
Registrant Street: 2155 E Warner Rd
Registrant City: Tempe
Registrant State/Province: Arizona
Registrant Postal Code: 85284
Registrant Country: US
Registrant Phone: +1.4806242599
Registrant Phone Ext:
Registrant Fax: 
Registrant Fax Ext:
Registrant Email: Select Contact Domain Holder link at https://www.godaddy.com/whois/results.aspx?domain=BITBYBITBOOK.COM
Registry Admin ID: Not Available From Registry
Admin Name: Registration Private
Admin Organization: Domains By Proxy, LLC
Admin Street: DomainsByProxy.com
Admin Street: 2155 E Warner Rd
Admin City: Tempe
Admin State/Province: Arizona
Admin Postal Code: 85284
Admin Country: US
Admin Phone: +1.4806242599
Admin Phone Ext:
Admin Fax: 
Admin Fax Ext:
Admin Email: Select Contact Domain Holder link at https://www.godaddy.com/whois/results.aspx?domain=BITBYBITBOOK.COM
Registry Tech ID: Not Available From Registry
Tech Name: Registration Private
Tech Organization: Domains By Proxy, LLC
Tech Street: DomainsByProxy.com
Tech Street: 2155 E Warner Rd
Tech City: Tempe
Tech State/Province: Arizona
Tech Postal Code: 85284
Tech Country: US
Tech Phone: +1.4806242599
Tech Phone Ext:
Tech Fax: 
Tech Fax Ext:
Tech Email: Select Contact Domain Holder link at https://www.godaddy.com/whois/results.aspx?domain=BITBYBITBOOK.COM
Name Server: NS23.DOMAINCONTROL.COM
Name Server: NS24.DOMAINCONTROL.COM
DNSSEC: unsigned
URL of the ICANN WHOIS Data Problem Reporting System: http://wdprs.internic.net/
>>> Last update of WHOIS database: 2023-10-28T16:34:50Z