When you think of how financial transactions work, what comes to mind is debited party (A), credited party (B) and transfer amount ($60). The transfer amount is debited from A's balance and added to B's balance and voila, transaction done.

Unfortunately, this is not how transactions work in the bitcoin blockchain. Also in contrast of what the terminology might suggest, bitcoin wallets balance is not included within the blockchain. so you can't take X amount from a person's balance and put it in another.

Before elaborating more on how bitcoin transactions work, let's explore the structure of bitcoin blocks and transactions.

If you open a block information page on a block explorer you'll see block information followed by a list of transactions included within the block. Once you click any of these transactions you'll be transfered to a page looking like this.

As per the image, two transfers have been made from:
address 1MvNWRsumsjvYYYP2wmNk4pSK7LrFr2Hr5
to two addresses
(14uCLm7uuda6kMP6PJrskTe3LgzFKMMa9Y, 16i8fvWqPdvcZCWnVfVoENEWvBVFzScsnB)
an amount of (40.558 BTC, 1 BTC) respectively. this information is an optimized version of the original data provided by the bitcoin blockchain to make it easier to comprehend bitcoin transaction. Here's raw transaction data from bitcoind

{
  "txid": "6433e021a03543efff936c58e055a13f9a64c22d4bfb5bcbfe836370713572d2",
  "hash": "6433e021a03543efff936c58e055a13f9a64c22d4bfb5bcbfe836370713572d2",
  "version": 1,
  "size": 258,
  "vsize": 258,
  "weight": 1032,
  "locktime": 0,
  
  "vin": [
    {
      "txid": "9516ff7b1841bc6d07681450af99ac83ad6c4a71f4b3f7a140c833f399f94e26",
      "vout": 0,
      "scriptSig": {
        "asm": "304502207307b0be78b7f6e4908f74df1856b5cd356bbd48072c89bf4f9ff41f8d3a5c02022100dfaa713cbd6797540a251728a2591f85f46bd7735344e82a6813228d08f56a56[ALL] 044b9f5b22f9fadf4e8f213fad6a1450ac9b5f2cfc85e3a8678b7aa71c5844fb36ae86009e1fca93e3e2e8c5dbf73475ba5d08ec6a86d78dcb680ec7afde0c47e8",
        "hex": "48304502207307b0be78b7f6e4908f74df1856b5cd356bbd48072c89bf4f9ff41f8d3a5c02022100dfaa713cbd6797540a251728a2591f85f46bd7735344e82a6813228d08f56a560141044b9f5b22f9fadf4e8f213fad6a1450ac9b5f2cfc85e3a8678b7aa71c5844fb36ae86009e1fca93e3e2e8c5dbf73475ba5d08ec6a86d78dcb680ec7afde0c47e8"
      },
      "sequence": 4294967295
    }
  ],
  
  "vout": [
    {
      "value": 40.55800000,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 2ac7795ef3514d61816ebad6f0691057702800c2 OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a9142ac7795ef3514d61816ebad6f0691057702800c288ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "14uCLm7uuda6kMP6PJrskTe3LgzFKMMa9Y"
        ]
      }
    },
    {
      "value": 1.00000000,
      "n": 1,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 3ea0163ba616c1c2353530897bc24addc42439f2 OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a9143ea0163ba616c1c2353530897bc24addc42439f288ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "16i8fvWqPdvcZCWnVfVoENEWvBVFzScsnB"
        ]
      }
    }
  ]
}

Notice the two fields vin, vout. These fields represent transaction inputs and transaction outputs. the total value of the input transactions should be equal to the value of the output transactions (41.558 = 1 + 40.558). So we can say value is being transferred from transaction inputs to transaction outputs. Transaction outputs are immutable, meaning you can't spend a part of output value you have to spend all of it or nothing. There's two outputs in the aforementioned transaction, first output has a value of 1 BTC, the other 40.588 BTC. in order to spend 1 BTC from the output you have to create a new output with the remaining value (40.588 BTC) credited to your address.  
When looking at the input transaction we'll find that it transfers a value of 41.588 BTC to 1MvNWRsumsjvYYYP2wmNk4pSK7LrFr2Hr5 (which is the debited address in the first transaction) from another transaction input. We can do that all the way to the coinbase block or genesis block. So, what we have is a chain of transactions.

In order to be able to spend a bitcoin, you'll have to prove that you own the address in a transaction output. So, assuming there's multiple transaction outputs with your address, your total wallet balance will the the total amount of these transaction outputs.
For example, You own an online shop which only receives payment in bitcoin and sells all items for the price of 0.05 each. Assuming you've sold 200 items, there should be 200 transaction outputs directed to your address. so your wallet will display a total balance should be 10 BTC. so when a bitcoin is transfered to you what really happens is that a new transaction output is genereted (mined) with your address in it. these UTXO (unspent transactions outputs) sum up to your balance.

In the previous examples, each UTXO holds a value of 0.05 BTC and we've already established that transaction outputs are immutable. So say you need to transfer a value of 1 BTC to another party, what your wallet will do is it will make a transaction with 20 of these UTXO as input transaction and a single output transaction for the receiving party (example with many inputs).

{
  "txid": "f57f37f703f17c6a44beb44739274e395ebe5869f6dbcec5e145b1d9d45cd1fb",
  "hash": "f57f37f703f17c6a44beb44739274e395ebe5869f6dbcec5e145b1d9d45cd1fb",
  "version": 1,
  "size": 2509,
  "vsize": 2509,
  "weight": 10036,
  "locktime": 0,
  "vin": [
    {
      "txid": "cf0f5728d6dc1be99da4143e78a84a97ae6c309b61d598938837e42f98b01405",
      "vout": 0,
      "scriptSig": {
        "asm": "3045022009cd670c02409742397c502d895dca4fb5975fa8da77fd1ced011871b83d9980022100ae104ebb25eb2bfb4ad7ba6fa551f73f415afe3907fa3ec59280c082609bbc0c[ALL] 0392d1f5e933ba23bfb6fb369e8c10865f28b9a17141f8a235a3b955252c1606fe",
        "hex": "483045022009cd670c02409742397c502d895dca4fb5975fa8da77fd1ced011871b83d9980022100ae104ebb25eb2bfb4ad7ba6fa551f73f415afe3907fa3ec59280c082609bbc0c01210392d1f5e933ba23bfb6fb369e8c10865f28b9a17141f8a235a3b955252c1606fe"
      },
      "sequence": 4294967295
    },
    {
      "txid": "e336776f181686c189c16a0214a110cda37d361c0874f25d8e1ff882c33cfd1b",
      "vout": 51,
      "scriptSig": {
        "asm": "304402203d0e193a3f7f3497cc335618122d9f315e6441a93061e938a9aa3e415d66ac8f02204d83ae8fed1a84493841def467839480895f0aa12046f764373f4ab05a1b6abb[ALL] 020d693219d96e8e6c7093f6a787e4c79f53e6255b1e4b0a2596741fe988523b32",
        "hex": "47304402203d0e193a3f7f3497cc335618122d9f315e6441a93061e938a9aa3e415d66ac8f02204d83ae8fed1a84493841def467839480895f0aa12046f764373f4ab05a1b6abb0121020d693219d96e8e6c7093f6a787e4c79f53e6255b1e4b0a2596741fe988523b32"
      },
      "sequence": 4294967295
    },
    {
      "txid": "24e21576b1a4b49abad44d94998733de64d18ff75de3b05d64f1ff540ed3df30",
      "vout": 0,
      "scriptSig": {
        "asm": "304402205866dcc9b1754ab59cfe660ce279eba509fa631c7cea375e17cd5e6206c2541402200f1f319bc9c8d4badcad59ea049fcd8a507a0bc025010e995fcb0f9f87c11842[ALL] 034ff39d603f5508b548810f94a4203be9f524e9bc3a01bf2d760b2865a7e9942d",
        "hex": "47304402205866dcc9b1754ab59cfe660ce279eba509fa631c7cea375e17cd5e6206c2541402200f1f319bc9c8d4badcad59ea049fcd8a507a0bc025010e995fcb0f9f87c118420121034ff39d603f5508b548810f94a4203be9f524e9bc3a01bf2d760b2865a7e9942d"
      },
      "sequence": 4294967295
    },
    {
      "txid": "e4d16dd878a93c643414d2aed85a97acf75a3d0db4815a778fa15d88fd8c283c",
      "vout": 54,
      "scriptSig": {
        "asm": "3045022100946f227d811c3e632b6fc7924eb1330a9bea883566c276081c8b5885739447b3022074eaf9996525a7f7d8405cfcbc7d90e4615295323496704015e465f2c93bd2c7[ALL] 035d7451bfdecbb6fc74e610527979fa6dc471095e334a3c8494d4daf07dbf6918",
        "hex": "483045022100946f227d811c3e632b6fc7924eb1330a9bea883566c276081c8b5885739447b3022074eaf9996525a7f7d8405cfcbc7d90e4615295323496704015e465f2c93bd2c70121035d7451bfdecbb6fc74e610527979fa6dc471095e334a3c8494d4daf07dbf6918"
      },
      "sequence": 4294967295
    },
    {
      "txid": "48151a6dce02ae974192597f501999b70962b76f3e77c5f5d0d04efc691c4648",
      "vout": 0,
      "scriptSig": {
        "asm": "304502200767799441ba5aef834be722e99e35e1b509bec755a707d99f6a64edc113109b022100d0b779a64119e823757cd29cd1c3cdc2e3df9ef73fd8afc1ebeba308d32de365[ALL] 024eda0bd35b5bdf4991f3c6f8f3bc918b7d28814c24ec51fa96030ff33959ce9a",
        "hex": "48304502200767799441ba5aef834be722e99e35e1b509bec755a707d99f6a64edc113109b022100d0b779a64119e823757cd29cd1c3cdc2e3df9ef73fd8afc1ebeba308d32de3650121024eda0bd35b5bdf4991f3c6f8f3bc918b7d28814c24ec51fa96030ff33959ce9a"
      },
      "sequence": 4294967295
    },
    {
      "txid": "7dbb1f8b3bd72e151bb08acde308b1926a14f680ff63f5d51c63aeb863d3e149",
      "vout": 36,
      "scriptSig": {
        "asm": "304402200b309f60f3c584d8e38aa27784d6b0309fe3a1b62e28b72559ff7e68a495598002201dab2fb0ff1a0c5296284eb1ff98f4dd07d00e62ff25994bc59759b6e18e5d81[ALL] 03b0c6cbcc6c371948a3c3cfd9f51c0ea2797c33b65275cc603ca4424fafa848a9",
        "hex": "47304402200b309f60f3c584d8e38aa27784d6b0309fe3a1b62e28b72559ff7e68a495598002201dab2fb0ff1a0c5296284eb1ff98f4dd07d00e62ff25994bc59759b6e18e5d81012103b0c6cbcc6c371948a3c3cfd9f51c0ea2797c33b65275cc603ca4424fafa848a9"
      },
      "sequence": 4294967295
    },
    {
      "txid": "558c39b20541fa71a96384a781f791b10cbd0c6d40818d7bb30cd734709ebc6a",
      "vout": 119,
      "scriptSig": {
        "asm": "3046022100b3ed5ded6d04434421abfae6f53c579cf09c817f537ee4067133380d00e669d1022100b2ca597de4b9654be18b34bc1c0d7957ebb40ab21822dd88edb4a56d4302829a[ALL] 0224e422b9109c5312d8dfe4071c6a7a72124b51dac24f31909e8e14d3148116f6",
        "hex": "493046022100b3ed5ded6d04434421abfae6f53c579cf09c817f537ee4067133380d00e669d1022100b2ca597de4b9654be18b34bc1c0d7957ebb40ab21822dd88edb4a56d4302829a01210224e422b9109c5312d8dfe4071c6a7a72124b51dac24f31909e8e14d3148116f6"
      },
      "sequence": 4294967295
    },
    {
      "txid": "651a9e345c1258101b3e7d6a515621ab403d2376d56b4dfb7bca5030431b4580",
      "vout": 14,
      "scriptSig": {
        "asm": "304402202e4df06960d3300a1b6fa3f45f276fcd141fb08b58f24cfd3e0d7f28fe6db2b6022009e28577dbeb60102d802973a5e32efc1704a10c437ac113cfde9d77dc2ec2a3[ALL] 022f6a2ced9aa09b9699eed52e215f61704ee52668206219097d2017cc5881d484",
        "hex": "47304402202e4df06960d3300a1b6fa3f45f276fcd141fb08b58f24cfd3e0d7f28fe6db2b6022009e28577dbeb60102d802973a5e32efc1704a10c437ac113cfde9d77dc2ec2a30121022f6a2ced9aa09b9699eed52e215f61704ee52668206219097d2017cc5881d484"
      },
      "sequence": 4294967295
    },
    {
      "txid": "57d1ce4604ef550f138736120acd7d579174ca5d63d793989ed5c7558297e8a6",
      "vout": 99,
      "scriptSig": {
        "asm": "3044022013498286c8eb0d09786eeb0d74692ce388216e997b9c84e648c27a27c15081760220225c5fff8bae49da0f91181783a2c90a1e248281c2c7d78f401b16b4130aeb9d[ALL] 0302f1e1b38296b21d906dce4cb7508d13c6d6583e4f6f4b19570a137167a49f83",
        "hex": "473044022013498286c8eb0d09786eeb0d74692ce388216e997b9c84e648c27a27c15081760220225c5fff8bae49da0f91181783a2c90a1e248281c2c7d78f401b16b4130aeb9d01210302f1e1b38296b21d906dce4cb7508d13c6d6583e4f6f4b19570a137167a49f83"
      },
      "sequence": 4294967295
    },
    {
      "txid": "1e36937308c603fad38b59c44417e430c1503c3911905bb12661da0987f905b8",
      "vout": 7,
      "scriptSig": {
        "asm": "304402205fefd28ca182438a928a9e717f5c3a0aa3deca64add07093d10e8f809966810502206a563ada56b699e49edafac5a045fecbe545a188c93a2295b1348a849484d28d[ALL] 034929e49b7a7e9b8693cfd32332d1d79e038ddef9250bf4f64a112dfe86276de8",
        "hex": "47304402205fefd28ca182438a928a9e717f5c3a0aa3deca64add07093d10e8f809966810502206a563ada56b699e49edafac5a045fecbe545a188c93a2295b1348a849484d28d0121034929e49b7a7e9b8693cfd32332d1d79e038ddef9250bf4f64a112dfe86276de8"
      },
      "sequence": 4294967295
    },
    {
      "txid": "d28728318820781d25237f14218a2502e1daa73d22f14b770977f939b6e694d4",
      "vout": 0,
      "scriptSig": {
        "asm": "3046022100eeca80071b636ebe1ea94dfd8a356e2ce070f16353bc20a9559df23b891ea5b8022100d5a9de22ae69e547f47b853ad066ac490a848075530acc96c14cc43737fc2f15[ALL] 04b39412c92685c8d354a009b1ab56b267d5701867d4962ee9b51900ff314e5dc31d2478a9ac05f9ac71796e815f6ed0cc1cc68312a7afdad71f130e0c835479a1",
        "hex": "493046022100eeca80071b636ebe1ea94dfd8a356e2ce070f16353bc20a9559df23b891ea5b8022100d5a9de22ae69e547f47b853ad066ac490a848075530acc96c14cc43737fc2f15014104b39412c92685c8d354a009b1ab56b267d5701867d4962ee9b51900ff314e5dc31d2478a9ac05f9ac71796e815f6ed0cc1cc68312a7afdad71f130e0c835479a1"
      },
      "sequence": 4294967295
    },
    {
      "txid": "633871e7bce7b0a36e293845b0d6605f05a093bed89f14480483d0c867914ed9",
      "vout": 0,
      "scriptSig": {
        "asm": "3046022100dd6bf12c7dcaa76fcf329a1d5316d0844a7c45f97c82268737f3a51d8d1def7e0221008958993a2cbe915f6aded38a746a615c40cb0c7436cdd20c90d8bb376e7ec524[ALL] 045643bdaddff3ea12b0024c2b127f0a67166c557045f06199742f8e7b4b62acb34cefa804b72c6f2b50654a03f526572a7874dd06e39ccb26eaca4790416d7b78",
        "hex": "493046022100dd6bf12c7dcaa76fcf329a1d5316d0844a7c45f97c82268737f3a51d8d1def7e0221008958993a2cbe915f6aded38a746a615c40cb0c7436cdd20c90d8bb376e7ec5240141045643bdaddff3ea12b0024c2b127f0a67166c557045f06199742f8e7b4b62acb34cefa804b72c6f2b50654a03f526572a7874dd06e39ccb26eaca4790416d7b78"
      },
      "sequence": 4294967295
    },
    {
      "txid": "8982584cab4f705bf2f0b7a79323ec3e9e624a5b0bb310e70d5fea59b00857e0",
      "vout": 0,
      "scriptSig": {
        "asm": "30450220223d2e68378036aae36fed04a01f13603e294dd6d5deb4ec028c41e1a62c1a77022100854f205f55e06367fff24055c32ad494477db2b58e08190bc86351b6af964289[ALL] 0385061e5cbcb6c97640438d1f9174fbbd864256597a28c0c340d3921b878a1456",
        "hex": "4830450220223d2e68378036aae36fed04a01f13603e294dd6d5deb4ec028c41e1a62c1a77022100854f205f55e06367fff24055c32ad494477db2b58e08190bc86351b6af96428901210385061e5cbcb6c97640438d1f9174fbbd864256597a28c0c340d3921b878a1456"
      },
      "sequence": 4294967295
    },
    {
      "txid": "36161f41c0d8cb3b88dd2a1e58c2f722cdd618ec7cf27ad41e9e21470b57e4e6",
      "vout": 36,
      "scriptSig": {
        "asm": "3046022100e656408e07c907b27a1e7a75fe38e24c13b0dace1dc45f0841c3ff77c114fa8e022100efa2b423abe240fe2663b8ae9d0f2d61ce09a016fd6c95e440506400eabde24b[ALL] 038141ca4d5e3b896de817c234acb292ae18a75cb2ecd604688be149c51f6585ee",
        "hex": "493046022100e656408e07c907b27a1e7a75fe38e24c13b0dace1dc45f0841c3ff77c114fa8e022100efa2b423abe240fe2663b8ae9d0f2d61ce09a016fd6c95e440506400eabde24b0121038141ca4d5e3b896de817c234acb292ae18a75cb2ecd604688be149c51f6585ee"
      },
      "sequence": 4294967295
    },
    {
      "txid": "bc87a169f4b4a4cdebb53099cb0853fcb17bc02f11cd6567959d2b2cfc6173fb",
      "vout": 11,
      "scriptSig": {
        "asm": "304602210091ac0eb50d08596918af24225d9adce1856454942c340c424970b25e20bb0237022100ee21cd30b0c7f0bfdccd58f9db0981874d76723d3e27a426554e80444ab627a6[ALL] 02921319d2464fe925ddec10bd59448e0d81692c03fae2d653feb469d02a1a6b0b",
        "hex": "49304602210091ac0eb50d08596918af24225d9adce1856454942c340c424970b25e20bb0237022100ee21cd30b0c7f0bfdccd58f9db0981874d76723d3e27a426554e80444ab627a6012102921319d2464fe925ddec10bd59448e0d81692c03fae2d653feb469d02a1a6b0b"
      },
      "sequence": 4294967295
    },
    {
      "txid": "d9fe433bc4325ac14df5aacb5cb0e8e090bde1f49057f6b8ce1e4d6d07981667",
      "vout": 14,
      "scriptSig": {
        "asm": "3045022100e09e3a02c76715c6bee36480fedc72c379d6330afb956cc88b84adf856d1ef1502205afd943bb96f9af811123ba220e15fd0ec1f1a8886b56715794f062d0c77f046[ALL] 032955f398c196f8a14c52e471eb600b8442ce1f4bef40f83ca035d26153ef81e9",
        "hex": "483045022100e09e3a02c76715c6bee36480fedc72c379d6330afb956cc88b84adf856d1ef1502205afd943bb96f9af811123ba220e15fd0ec1f1a8886b56715794f062d0c77f0460121032955f398c196f8a14c52e471eb600b8442ce1f4bef40f83ca035d26153ef81e9"
      },
      "sequence": 4294967295
    }
  ],
  "vout": [
    {
      "value": 0.00024779,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 f0723db85510b942c331dd70cc10f876fdc841f6 OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914f0723db85510b942c331dd70cc10f876fdc841f688ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "1NvN2egU5PbH1Sj4D8UfpLWvASq2emkH8U"
        ]
      }
    },
    {
      "value": 0.11000000,
      "n": 1,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 e9b6dcfc6bd4d31b2c7298ac69ba71056eea6f71 OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914e9b6dcfc6bd4d31b2c7298ac69ba71056eea6f7188ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "1NJmWFrvGHGJLD3F78azb73BgQ3JFTNdSk"
        ]
      }
    }
  ]
}

In real life, UTXO amounts will vary and usually your wallet has an algorithm for optimizing selected UTXO according to transaction amount.