• Banner

Active filters
  • Categories: Artificial intelligence (AI)
  • Categories: Instruments
  • Categories: Programmer

Reference: RBD-0234

Brand: SparkFun Electronics

LCD Cape - pcDuino V3 (1024x600 7" LVDS)

(0)
Description: This is a 7" LVDS LCD Cape for the pcDuino V3  with a 1024x600 screen resolution and capacitive touch from  LinkSprite. This massive screen is a great addition for the  pcDuino V3 that compliments its extreme versatility as a mini  PC development platform. 
BDT 7,500.00
BDT 7,500.00 tax incl.
BDT 7,500.00 tax excl.
BDT 7,500.00 tax excl.
BDT 7,500.00 tax incl.
BDT 7,500.00 tax incl.
BDT 0.00 Tax
BDT 7,500.00 tax excl.
BDT 7,500.00 tax excl.
BDT 0.00 Tax
BDT 7,500.00 tax incl.
More
Last items in stock
In stock: 1

Reference: RBD-0165

USB Logic Analyzer

(0)
Description: This is a powerful logic analyzer in a very small anodized aluminum package from Saleae Logic. We absolutely love the simplistic, sleek design with light-weight software and a high-quality finish. Who needs 50+ connections when you’re troubleshooting I2C? With USB connectivity, you can analyze up to 8 digital waveforms and timing information...
BDT 15,400.00
BDT 15,400.00 tax incl.
BDT 15,400.00 tax excl.
BDT 15,400.00 tax excl.
BDT 15,400.00 tax incl.
BDT 15,400.00 tax incl.
BDT 0.00 Tax
BDT 15,400.00 tax excl.
BDT 15,400.00 tax excl.
BDT 0.00 Tax
BDT 15,400.00 tax incl.
More
Out-of-Stock
In stock: 0

Reference: RBD-1373

NVIDIA Jetson Nano Developer Kit

(0)
GPU: 128-core NVIDIA Maxwell™ GPU CPU: Quad-core ARM® A57 CPU Memory: 4 GB 64-bit LPDDR4 Storage: 16GB eMMC 5.1 flash Video Encoder: 4K @30(H.264/H.265) Video Decoder: 4K @60(H.264/H.265) Camera: 12 lanes (3×4 or 4×2) MIPI CSI-2 DPHY 1.1(1.5Gbps) Connectivity: Gigabit Ethernet Display: HDMI 2.0 or DP1.2 |eDP 1.4| DSI (1x2) UPHY: 1x1/2/4 PCIE, 1xUSB3.0,...
BDT 45,990.00
BDT 45,990.00 tax incl.
BDT 45,990.00 tax excl.
BDT 45,990.00 tax excl.
BDT 45,990.00 tax incl.
BDT 45,990.00 tax incl.
BDT 0.00 Tax
BDT 45,990.00 tax excl.
BDT 45,990.00 tax excl.
BDT 0.00 Tax
BDT 45,990.00 tax incl.
More
In-Stock
In stock: 6

Reference: RBD-0412

PICkit3 Microchip MPLAB PICkit 3 PIC In-Circuit Programmer Debugger for PIC and dsPIC Flash Chips

(0)
Microchip's PICkit3 In-Circuit Debugger/Programmer uses in-circuit debugging logic incorporated into each chip with Flash memory to provide a low-cost hardware debugger and programmer. The MPLAB PICkit3 allows debugging and programming of PIC® and dsPIC® Flash microcontrollers at a most affordable price.
BDT 2,500.00
BDT 2,500.00 tax incl.
BDT 2,500.00 tax excl.
BDT 2,500.00 tax excl.
BDT 2,500.00 tax incl.
BDT 2,500.00 tax incl.
BDT 0.00 Tax
BDT 2,500.00 tax excl.
BDT 2,500.00 tax excl.
BDT 0.00 Tax
BDT 2,500.00 tax incl.
More
Out-of-Stock
In stock: -2

Reference: RBD-0180

Brand: SparkFun Electronics

Makey Makey Kit

(0)
Description: This is the same product as the Makey Makey Standard Kit. The difference is this version comes in fancy clamshell packaging meant for our distributors that need it. Regular customers are welcome to order, but we want to limit the amount of extra packaging finding its way into the trash heap.
BDT 5,500.00
BDT 5,500.00 tax incl.
BDT 5,500.00 tax excl.
BDT 5,500.00 tax excl.
BDT 5,500.00 tax incl.
BDT 5,500.00 tax incl.
BDT 0.00 Tax
BDT 5,500.00 tax excl.
BDT 5,500.00 tax excl.
BDT 0.00 Tax
BDT 5,500.00 tax incl.
More
Last items in stock
In stock: 1

Reference: RBD-1549

NVIDIA Jetson Nano 2GB Developer Kit

(0)
Micro-USB: 5V 2A USB C: 5V 3A. 128-core NVIDIA Maxwell GPU Quad-core ARM A57 2 GB 64-bit LPDDR4 Connectivity by Gigabit Ethernet (RJ45)
BDT 10,990.00
BDT 10,990.00 tax incl.
BDT 10,990.00 tax excl.
BDT 10,990.00 tax excl.
BDT 10,990.00 tax incl.
BDT 10,990.00 tax incl.
BDT 0.00 Tax
BDT 10,990.00 tax excl.
BDT 10,990.00 tax excl.
BDT 0.00 Tax
BDT 10,990.00 tax incl.
More
Out-of-Stock
In stock: 0

Reference: RBD-0188

USB Saleae Compatible 24MHz 8Channel Logic Analyzer Latest Support 1.1.15

(0)
Logical light indication: a small light indicate CHO electrical level. Input feature: 5PF,100K Ohm. USB power supply; USB logic analyzer for monitoring, analyzing and debugging digital circuits 8-Channels USB logic analyzer with a 24Mhz sampling frequency Can analyze UART, IIC, and SPI, etc automatically Great for MCU, ARM system and FPGA development...
BDT 1,240.00
BDT 1,240.00 tax incl.
BDT 1,240.00 tax excl.
BDT 1,240.00 tax excl.
BDT 1,240.00 tax incl.
BDT 1,240.00 tax incl.
BDT 0.00 Tax
BDT 1,240.00 tax excl.
BDT 1,240.00 tax excl.
BDT 0.00 Tax
BDT 1,240.00 tax incl.
More
In-Stock
In stock: 17

Reference: RBD-1850

Brand: Raspberry Pi Official

Raspberry Pi 400 4GB RAM Complete Set

(0)
১ টি রাস্পবেরি পাই 400 (Made in UK) RAM: 4GB (Fixed) একসাথে দুটি HDMI মনিটর লাগানো যায়।   রাস্পবেরি পাই এর ইউএসবি -সি পাওয়ার এডাপটার সুইচ সহ।  স্যানডিস্ক ব্রান্ডের জেনুইন ৩২ জিবি মেমরি কার্ড প্রি-ইনস্টলড অপারেটিং সিস্টেম সহ।  বিল্ট ইন Wi-Fi & Bluetooth গিগাবিট ইথারনেট পোর্ট।   ২ টি USB 3.0 & ১ টি USB 2.0
BDT 14,820.00
BDT 14,820.00 tax incl.
BDT 14,820.00 tax excl.
BDT 14,820.00 tax excl.
BDT 14,820.00 tax incl.
BDT 14,820.00 tax incl.
BDT 0.00 Tax
BDT 14,820.00 tax excl.
BDT 14,820.00 tax excl.
BDT 0.00 Tax
BDT 14,820.00 tax incl.
More
In-Stock
In stock: 6

Reference: RBD-1102

ST-Link V2 Programmer For STM8 and STM32

(0)
PCB installed inside of aluminum alloy U disk shell, portable, safe and reliable! Interface definition directly marked on the shell, clear, convenient and practical! 5V, 3.3V offers at the same time, allowing you to program your target board with both 5V and 3.3V Shell characters using laser engraving, never fade off! Permanent clarity! 500MA internal...
BDT 585.00
BDT 585.00 tax incl.
BDT 585.00 tax excl.
BDT 585.00 tax excl.
BDT 585.00 tax incl.
BDT 585.00 tax incl.
BDT 0.00 Tax
BDT 585.00 tax excl.
BDT 585.00 tax excl.
BDT 0.00 Tax
BDT 585.00 tax incl.
More
In-Stock
In stock: 48

Reference: RBD-0204

Hantek 6022BE PC Oscilloscope

(0)
Hantek 6022BE PC Oscilloscope
BDT 9,890.00
BDT 9,890.00 tax incl.
BDT 9,890.00 tax excl.
BDT 9,890.00 tax excl.
BDT 9,890.00 tax incl.
BDT 9,890.00 tax incl.
BDT 0.00 Tax
BDT 9,890.00 tax excl.
BDT 9,890.00 tax excl.
BDT 0.00 Tax
BDT 9,890.00 tax incl.
More
In Stock
In stock: 13

Reference: RBD-1142

Brand: Raspberry Pi Official

Raspberry Pi 4 Computer Complete Set Pack-2

(0)
১ টি রাস্পবেরি পাই 4 (Made in UK) RAM: 1GB, 2GB, 4GB, 8GB (পছন্দ করে নিতে পারবেন) একসাথে দুটি HDMI মনিটর লাগানো যায়।   ১ টি কুলিং Acrylic ফ্যান কেস।  রাস্পবেরি পাই এর হিট সিংক।  রাস্পবেরি পাই এর ইউএসবি -সি পাওয়ার এডাপটার সুইচ সহ।  ট্রান্সসেন্ড অথবা স্যানডিস্ক ব্রান্ডের জেনুইন ১৬ জিবি অথবা ৩২ জিবি মেমরি কার্ড প্রি-ইনস্টলড অপারেটিং সিস্টেম সহ।  বিল্ট ইন...
BDT 18,070.00
BDT 18,070.00 tax incl.
BDT 18,070.00 tax excl.
BDT 18,070.00 tax excl.
BDT 18,070.00 tax incl.
BDT 18,070.00 tax incl.
BDT 0.00 Tax
BDT 18,070.00 tax excl.
BDT 18,070.00 tax excl.
BDT 0.00 Tax
BDT 18,070.00 tax incl.
More
Last items in stock
In stock: 1

Reference: RBD-1103

ALTERA Mini USB Blaster Cable for CPLD FPGA NIOS JTAG Programmer

(0)
Stably support SignalTap II embedded logic analyzer function, no mistake while crawling data. Fully support all Altera products such as CPLD: MAX3000, MAX7000, MAX9000 and MAXII. FPGA: Stratix, StratixII, StratxIII, Cyclone, CycloneII, CycloneIII, ACEX1K, APEX20K and FLEX10K etc. Active serial configuration device: EPCS1, EPCS4, EPCS16, EPCS64 etc....
BDT 770.00
BDT 770.00 tax incl.
BDT 770.00 tax excl.
BDT 770.00 tax excl.
BDT 770.00 tax incl.
BDT 770.00 tax incl.
BDT 0.00 Tax
BDT 770.00 tax excl.
BDT 770.00 tax excl.
BDT 0.00 Tax
BDT 770.00 tax incl.
More
In-Stock
In stock: 29

Reference: RBD-0227

JF-0530B Pull Push Type Electric Solenoid Electromagnet 10mm 5N DC6V

(0)
Model: DC 5V 10mm 5N Rated Operating Voltage (VDC): 5 Operation Mode: Push-Pull (Normally Closed) Holding Force (N): 5 Weight:33 gm
BDT 480.00
BDT 480.00 tax incl.
BDT 480.00 tax excl.
BDT 480.00 tax excl.
BDT 480.00 tax incl.
BDT 480.00 tax incl.
BDT 0.00 Tax
BDT 480.00 tax excl.
BDT 480.00 tax excl.
BDT 0.00 Tax
BDT 480.00 tax incl.
More
In-Stock
In stock: 29

Reference: 1141

Brand: Raspberry Pi Official

Raspberry Pi 4 Computer Complete Set

(0)
১ টি রাস্পবেরি পাই 4 (Made in UK) RAM: 8GB  একসাথে দুটি HDMI মনিটর লাগানো যায়।   ১ টি কুলিং অ্যালুমিনিয়াম মেটাল ফ্যান কেস।  রাস্পবেরি পাই এর হিট সিংক।  রাস্পবেরি পাই এর ইউএসবি -সি পাওয়ার অফিসিয়াল এডাপটার।  ট্রান্সসেন্ড অথবা স্যানডিস্ক ব্রান্ডের জেনুইন ৬৪ জিবি মেমরি কার্ড প্রি-ইনস্টলড অপারেটিং সিস্টেম সহ।  বিল্ট ইন Wi-Fi & Bluetooth গিগাবিট ইথারনেট...
BDT 18,510.00
BDT 18,510.00 tax incl.
BDT 18,510.00 tax excl.
BDT 18,510.00 tax excl.
BDT 18,510.00 tax incl.
BDT 18,510.00 tax incl.
BDT 0.00 Tax
BDT 18,510.00 tax excl.
BDT 18,510.00 tax excl.
BDT 0.00 Tax
BDT 18,510.00 tax incl.
More
Product available with different options
In stock: 0

Reference: RBD-1104

USBTiny AVR ISP Programmer Bootloader For Arduino IDE

(0)
Isp interface: 6 PIN Isp interface: 10 PIN Power supply options: USB power Power supply options: external power supply (remove jumper cap)
BDT 900.00
BDT 900.00 tax incl.
BDT 900.00 tax excl.
BDT 900.00 tax excl.
BDT 900.00 tax incl.
BDT 900.00 tax incl.
BDT 0.00 Tax
BDT 900.00 tax excl.
BDT 900.00 tax excl.
BDT 0.00 Tax
BDT 900.00 tax incl.
More
In-Stock
In stock: 9

Reference: RBD-2381

3D AI Face Recognition HLK-TX510 Test kit 3D Binocular Camera Live Detection Module

(0)
HLK-TX510 is a module developed based on artificial intelligence chip TX510, AI computing power 1.2T@8bit/9.6T@binary, supports mixed precision, can quickly detect faces, supports 3D living detection, 3D face recognition, infrared living detection, Visible light live detection, etc., can resist two-dimensional attacks such as photos and videos, and...
BDT 8,250.00
BDT 8,250.00 tax incl.
BDT 8,250.00 tax excl.
BDT 8,250.00 tax excl.
BDT 8,250.00 tax incl.
BDT 8,250.00 tax incl.
BDT 0.00 Tax
BDT 8,250.00 tax excl.
BDT 8,250.00 tax excl.
BDT 0.00 Tax
BDT 8,250.00 tax incl.
More
In stock
In stock: 5

Reference: RBD-1106

XGecu Super Mini Pro T48 Universal Programmer

(0)
XGecu Super Mini Pro T48 Universal Programmer
BDT 7,590.00
BDT 7,590.00 tax incl.
BDT 7,590.00 tax excl.
BDT 7,590.00 tax excl.
BDT 7,590.00 tax incl.
BDT 7,590.00 tax incl.
BDT 0.00 Tax
BDT 7,590.00 tax excl.
BDT 7,590.00 tax excl.
BDT 0.00 Tax
BDT 7,590.00 tax incl.
More
In-Stock
In stock: 4

Reference: RBD-0280

Mini Breadboard

(0)
Tie-points: 170 (10×17) Size: 48 x 35 x 10 mm(LxWxH). Use: experimental, testing, robot Matching jumper, diameter 0.8mm Phosphor bronze nickel plated spring clips Accepts a variety of wire sizes (29-20 the AWG) **1 pcs Random Color
BDT 45.00
BDT 45.00 tax incl.
BDT 45.00 tax excl.
BDT 45.00 tax excl.
BDT 45.00 tax incl.
BDT 45.00 tax incl.
BDT 0.00 Tax
BDT 45.00 tax excl.
BDT 45.00 tax excl.
BDT 0.00 Tax
BDT 45.00 tax incl.
More
In-Stock
In stock: 633

Reference: RBD-1422

Pixy2.1 CMUcam5 Smart Vision Sensor

(0)
Processor: NXP LPC4330, 204 MHz, dual core Image sensor: Aptina MT9M114, 1296×976 resolution with integrated image flow processor Lens field-of-view: 80 degrees horizontal, 40 degrees vertical Power consumption: 140 mA typical Power input: USB input (5V) or unregulated input (6V to 10V) RAM: 264K bytes Flash: 2M bytes
BDT 12,950.00
BDT 12,950.00 tax incl.
BDT 12,950.00 tax excl.
BDT 12,950.00 tax excl.
BDT 12,950.00 tax incl.
BDT 12,950.00 tax incl.
BDT 0.00 Tax
BDT 12,950.00 tax excl.
BDT 12,950.00 tax excl.
BDT 0.00 Tax
BDT 12,950.00 tax incl.
More
In-Stock
In stock: 4

Reference: RBD-1212

USB to Serial RS232 DB9 Converter Cable

(0)
Single crystal 12M Tablet 340 USB port to serial port communication. USB1.1/2.0 compliant solution. Built-in 128 byte TX/512 byte RX buffer. Supports auto-Handshake Protocol. Support Win95/98/98se/ME/2000/XP/win7 32bit 64bit/Vista/supports full speed USB data transfer protocol. Design of electromagnetic interference. Data Exchange application. CH340 USB...
BDT 299.00
BDT 299.00 tax incl.
BDT 299.00 tax excl.
BDT 299.00 tax excl.
BDT 299.00 tax incl.
BDT 299.00 tax incl.
BDT 0.00 Tax
BDT 299.00 tax excl.
BDT 299.00 tax excl.
BDT 0.00 Tax
BDT 299.00 tax incl.
More
In-Stock
In stock: 59

Reference: RBD-0284

5.8GHz Circular Polarized Mushroom Antenna RP-SMA Set Tx/Rx for FPV Multicopter

(0)
Gain: 2.0dBi-2.5dBi Antenna connector: RP-SMA Male Connector Standing wave ratio(SWR): <1.5 Weight: TxA10.3g, RxA 11.5g TxA is a circular-polarized Omni antenna with three lobes RxA is a circular-polarized Omni antenna with four lobes
BDT 880.00
BDT 880.00 tax incl.
BDT 880.00 tax excl.
BDT 880.00 tax excl.
BDT 880.00 tax incl.
BDT 880.00 tax incl.
BDT 0.00 Tax
BDT 880.00 tax excl.
BDT 880.00 tax excl.
BDT 0.00 Tax
BDT 880.00 tax incl.
More
In-Stock
In stock: 6

Reference: RBD-1974

Brand: DFRobot

Gravity Huskylens AI Camera Vision Sensor with Silicone Case

(0)
One-click learn Machine Learning Enabled Onboard Screen Extreme Performance
BDT 10,990.00
BDT 10,990.00 tax incl.
BDT 10,990.00 tax excl.
BDT 10,990.00 tax excl.
BDT 10,990.00 tax incl.
BDT 10,990.00 tax incl.
BDT 0.00 Tax
BDT 10,990.00 tax excl.
BDT 10,990.00 tax excl.
BDT 0.00 Tax
BDT 10,990.00 tax incl.
More
Last items in stock
In stock: 1

Reference: RBD-1110

AVRISP Atmel STK500 AVR programmer USB Atmega Attiny

(0)
Supports a wide range of ATMEL AVR microcontroller. Works with AVR Studio or WINAVR(GCC) Works with ATMEL AVR Studio 4.13
BDT 2,900.00
BDT 2,900.00 tax incl.
BDT 2,900.00 tax excl.
BDT 2,900.00 tax excl.
BDT 2,900.00 tax incl.
BDT 2,900.00 tax incl.
BDT 0.00 Tax
BDT 2,900.00 tax excl.
BDT 2,900.00 tax excl.
BDT 0.00 Tax
BDT 2,900.00 tax incl.
More
In-Stock
In stock: 8

Reference: RBD-2617

CanMV K210 AI Vision Sensor

(0)
Unlock AI vision with this powerful module: Face recognition, color detection, object identification, and more with deep learning AI. DIY-friendly and open-source: Perfect for makers and developers with easy installation and open-source code. Compact and portable: Take your AI projects anywhere with its lightweight and small size. High-performance...
BDT 15,500.00
BDT 15,500.00 tax incl.
BDT 15,500.00 tax excl.
BDT 15,500.00 tax excl.
BDT 15,500.00 tax incl.
BDT 15,500.00 tax incl.
BDT 0.00 Tax
BDT 15,500.00 tax excl.
BDT 15,500.00 tax excl.
BDT 0.00 Tax
BDT 15,500.00 tax incl.
More
Last items in stock
In stock: 1

Reference: RBD-1139

PICKIT 3.5 Compatible Programmer / DebuggerPICKIT 3.5 Compatible Programmer / Debugger

(0)
Type: Debugger/Programmer Tool/Board Application: Debugging/Programming MCU Supported Families: Flash-based PIC MCUs Core Architecture: PIC, dsPIC
BDT 4,920.00
BDT 4,920.00 tax incl.
BDT 4,920.00 tax excl.
BDT 4,920.00 tax excl.
BDT 4,920.00 tax incl.
BDT 4,920.00 tax incl.
BDT 0.00 Tax
BDT 4,920.00 tax excl.
BDT 4,920.00 tax excl.
BDT 0.00 Tax
BDT 4,920.00 tax incl.
More
In-Stock
In stock: 4

Reference: RBD-0319

K Type Thermocouple Sensor Probe for Temperature Controller

(0)
Type K Type.  Mounting thread: M6  Temperature Range:0-600°C. RoboticsBD
BDT 300.00
BDT 300.00 tax incl.
BDT 300.00 tax excl.
BDT 300.00 tax excl.
BDT 300.00 tax incl.
BDT 300.00 tax incl.
BDT 0.00 Tax
BDT 300.00 tax excl.
BDT 300.00 tax excl.
BDT 0.00 Tax
BDT 300.00 tax incl.
More
In-Stock
In stock: 113

Reference: RBD-2627

01Studio pyAI- K210 Intelligence Machine Learning AI Development Board

(0)
Unlock AI Potential: Develop intelligent applications with this feature-rich AI development board. RISC-V Dual-Core Processor: Delivers efficient processing power for demanding AI tasks. pyboard Compatible: Integrates seamlessly with existing tools and libraries. Auto-Download Circuit: Simplifies programming and firmware updates. User-Friendly Design:...
BDT 14,500.00
BDT 14,500.00 tax incl.
BDT 14,500.00 tax excl.
BDT 14,500.00 tax excl.
BDT 14,500.00 tax incl.
BDT 14,500.00 tax incl.
BDT 0.00 Tax
BDT 14,500.00 tax excl.
BDT 14,500.00 tax excl.
BDT 0.00 Tax
BDT 14,500.00 tax incl.
More
Last items in stock
In stock: 1

Reference: RBD-1700

Brand: Waveshare

ST-LINK V2 Mini- STM Programmers & Debuggers

(0)
Mini ST-LINK/V2  Small single board Extreme low cost solution  In-circuit debugger/programmer  STM8 STM32.
BDT 900.00
BDT 900.00 tax incl.
BDT 900.00 tax excl.
BDT 900.00 tax excl.
BDT 900.00 tax incl.
BDT 900.00 tax incl.
BDT 0.00 Tax
BDT 900.00 tax excl.
BDT 900.00 tax excl.
BDT 0.00 Tax
BDT 900.00 tax incl.
More
Out-of-Stock
In stock: -2

Reference: RBD-0383

ADS1115 16-Bit ADC- 4 Channel with Programmable Gain Amplifier

(0)
Wide Supply Range: 2.0v To 5.5v Low Current Consumption Continuous Mode: Only 150µa Single-shot Auto Shut-down Programmable Data Rate: 8SPS to 860SPS It has Internal low-drift voltage reference
BDT 410.00
BDT 410.00 tax incl.
BDT 410.00 tax excl.
BDT 410.00 tax excl.
BDT 410.00 tax incl.
BDT 410.00 tax incl.
BDT 0.00 Tax
BDT 410.00 tax excl.
BDT 410.00 tax excl.
BDT 0.00 Tax
BDT 410.00 tax incl.
More
In-Stock
In stock: 25

Reference: RBD-2830

Brand: DFRobot

Maixduino AI Development Kit K210 RISC-V AI + IoT ESP32

(0)
Based on K210 RISC-V AI processor, the Maixduino AI development board comes with MI AI module and ESP32 module for WiFi and Bluetooth connectivity in the Arduino UNO form factor. K210 comes with a dual-core processor chip with independent FPU, 64 bits CPU bit width, 8 MB on-chip SRAM, 400 adjustable nominal frequency, and double-precision FPU supporting...
BDT 9,500.00
BDT 9,500.00 tax incl.
BDT 9,500.00 tax excl.
BDT 9,500.00 tax excl.
BDT 9,500.00 tax incl.
BDT 9,500.00 tax incl.
BDT 0.00 Tax
BDT 9,500.00 tax excl.
BDT 9,500.00 tax excl.
BDT 0.00 Tax
BDT 9,500.00 tax incl.
More
Last items in stock
In stock: 1

Follow us on Facebook