Technical deep

Pair programming
    - State what you know
    - Ask questions
    - Start Simple
    - Should be extendable
    - Write tests

Data structure
-------------------
tree ( Eg: Filesystem tree, PATH /usr/home/tom)
    -undirected graph , acyclic(no cycle) connected graph
    -n nodes n- 1 edges
    -node connected by one path
    -Root, parent, child, key, edges, leaf nodes(bottom , no child), sub tree

    Binary Tree:
        -Only max two children
            Binary search tree
                -lesser on left, bigger on right
    Uses:
        syntax trees (compilers and calculators)

    On insertion:
        if < on left
        if > on right
        if same do nothing

    on removal:
        find:
            reached null node (not found)
            == 0 found
            <  go to left
            > go to right
        replace to successor
            if leaf - no effect
            if it has right node
            if it has left node
            if it has both - find smallest on right || find largest on left

    Traversal:
        Preorder - print before
        In order - print in middle
        post order - print after
        level order - print level by level - BFS - using queue

Hashing:

    DS that map -> key and values
    keys - hasing - unique - fixed range
    uses:
        check words frequencies

Heap:
    binary tree:
        1.Max heap - root node max of all nodes
        2. min heap - root node min of all nodes

Dikistra Algo:
    find value shortest path using its distance between two nodes

Algorithms
---------------
    - Sorting and Searching
Merge Sort
Quick Sort
Insertion Sort
selection Sort
Bubble Sort
radix sort

    - Bit Manipulation
    - Basic Co-ordinate geometry - Manhattan Distance, Closest Point Pair
    - Divide and Conquer
    - Greedy
    - Dynamic Programming - Extremely important
    - Probability and basic Number Theory
    - Try famous Problems for solutions

Other languages
    - Angular - Learn all basics

Problems:
    - Facebook mutual friends create design
    - Software excelence
    - tic tak toe gam
    - data structures used for file search and tree traversal and insertion
    - app like split wise

Social Cause:
    - caste based system - DONe
    - LBGT - DONE
    - women in tech - DONE

Technology Depth
    - Microservices - DONE ( Highly maintanable and testable, loosly couples, independent deployement)
    - OS - DONE - Threads, Processes (Instance of computer program, it can have single or multiple threads) - DONE
    - Memory Management - DONE- Single contiguous, partitioned , paged, segmented => First(first free) , best(smallest process can adopt), worst (largest), next fit(after first it start from where it left from) - DONE
    - Scalability Issues - DONE -(Architecture issues(Microservices, load balancer..etc), database scalling(split database, replicas, sharding..etc), CPU Bound(heavy calulcation, no caching, no async could cuase it), IO bound(more time than cpu process, SSD could fix))
    - Linux booting process
        BIOS(basic i/o system) =>  search ->load -> execute -> MBR boot loader programs
        MBL(master boot loader) => MBL -> executes GRUB boot loader
        GRUB(Grand Unified boot loader) => loads ->execute ->Kernal (If multple kernal images it will show on system)
        Kernal => execute init() program -> Mount FS and initilize RAM and init other hardwares
        Init => execute run level programs
        Run level Programs => executes startups ..etc
    - Linux commands
        ps => get processes
        grep => print by regular expression
        sed => replace strings in text file
        ifconfig, ls,rm,find,touch,vi,emacs,rmdir,chmod,chown, init 0, init 1, init 6

    - CSS3, Saas - DONE - can import, var, reuse ,strcutured way of writing css
    - Docker - Hypervisor (separate os for each machine and fixed resouces), Docker engine talks directly to Host os and docker file -> images -> containers 
    - Git commands - DONE
    -Browser background:
        DNS look up to get IP
        Browser cache -> System Cache -> router Cache -> resolver (ISP) Cache ->
        ROOT Server (8 server all over the world) -> It gives top level domain -> (.com) -> that server -> Name server with its ip ->it gives ip address for that site
        Resolver -> OS -> Browser IP received ->
        Make http request to server -> request -> server Agreed and send Acknowldge ->client agreed and send ack -> connection estableshed -> server sends data with headers to browser then browser shows it